JP3040984B1 - Bistatic radar system - Google Patents

Abstract

A bistatic radar system includes:
While the transmitting station or the receiving station moves, the position of the target is observed. SOLUTION: A transmitting station 60 and a receiving station 62 have self-position detecting units 30 and 32, respectively. In addition, the transmitting station 60 and the receiving station 62 have clocks 22 and 26, respectively, whose time is strictly adjusted to each other. Data transmitting section 66 of transmitting station 60
Converts a transmission station data such as a radar beam transmission schedule and a movement position of the own station into a binary code, and modulates a radar pulse based on the binary code. The receiving station 62 receives the echo 48 from the modulated radar beam target 46,
The data receiving unit 70 extracts transmission station data from the echo 48, and the target position calculation unit 42 calculates the position of the target using the position of the transmission station, the echo receiving direction, and the delay time from beam emission to echo reception.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bistatic radar system, and more particularly to a bistatic radar system in which either a transmitting station or a receiving station or both are arranged on a mobile body.

[0002]

2. Description of the Related Art Conventionally, there has been a bistatic radar in which a transmitting station for transmitting radar waves and a receiving station for receiving an echo emitted from the transmitting station and reflected by a target are separated from each other, that is, located at different places. Are known.

FIG. 15 is a schematic configuration diagram of this conventional bistatic radar system. The transmitting station 2 and the receiving station 4 are fixed stations, respectively.
Can be known relative to the own station.

[0004] The clocks of the two stations are synchronized. For example, both stations have atomic clocks that are time-aligned with each other. The transmitting station 2 transmits a radar pulse based on its own clock, while the receiving station 4
A time schedule indicating when and in what direction the transmitting station 2 emits the radar beam is notified via the communication line 6 in advance. The receiving station 4
From the difference between the transmission timing of the radar pulse on the transmission time schedule and the echo reception time based on the clock of the own station, from the time when the radio wave is emitted from the transmission station until it is reflected by the target and reaches the reception station The path length of the radar beam can be known. The receiving station transmits the beam of the transmitting station (for example, azimuth and elevation), the path length of the radar beam emitted from the transmitting station to be reflected by the target and reaches the receiving station, the echo receiving direction, and the transmitting station and its own station. From the positional relationship, the position of the target can be calculated.

Since the receiving station 4 does not require a transmitting device, the bistatic radar system has features such as a small size and light weight, and no interference with the vicinity of the receiving station. Utilizing such features, a plurality of receiving stations are arranged around one transmitting station, and a system for performing observation using radar waves of the transmitting station at each receiving station is simply or economically constructed. be able to.

[0006]

However, in the conventional bistatic radar system, the positional relationship between the transmitting station 2 and the receiving station 4 is fixed, and one of the transmitting station and the receiving station is a mobile station, for example. When the transmitting station and the receiving station are mounted on a moving body such as an aircraft or a ship, their positional relationship is not kept constant, so that the position of the target cannot be specified. That is, the conventional bistatic radar system has a problem that it cannot be used when the transmitting station and the receiving station can move.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and a bistatic radar capable of observing the position of a target even when either or both of a transmitting station and a receiving station are movable stations. The purpose is to provide a system.

[0008]

A first bistatic radar system according to the present invention has a transmitting station arranged on a mobile body, and a self-position detecting section for detecting a moving position of the own station;
A clock that measures the emission time of the search radio wave that is kept synchronized with the time of the reception station, and a data transmission unit that transmits transmission station data including the movement position and the emission time of the search radio wave to the reception station The receiving station, based on a positional relationship between the transmitting station and its own station, a time difference between the emission time of the search radio wave and the echo reception time, and the echo reception direction (azimuth and elevation). And a target position calculating unit for calculating the position of the target.

[0009] A second bistatic radar system according to the present invention is characterized in that the transmitting station measures the emission time of the search radio wave while maintaining the synchronism with the time of the receiving station; A data transmitting unit for transmitting transmitting station data including the time of launch of the search radio wave, wherein the receiving station is arranged on a mobile object, and a self-position detecting unit for detecting a moving position of the own station; A target position calculating unit that calculates the position of the target based on a positional relationship between the target station and the local station, a time difference between the emission time of the search radio wave and the echo reception time, and an echo reception direction.

[0010] In a third bistatic radar system according to the present invention, there is provided an information center interposed in a communication path of the transmitting station data from the transmitting station to the receiving station, wherein the information center is provided from the transmitting station. Wherein the receiving station reads out and acquires the transmitting station data stored in the information center.

[0011] In a fourth bistatic radar system according to the present invention, the data transmitting section has a modulating section for modulating the search radio wave in accordance with the transmitting station data coded in N-ary (N ≧ 2). The receiving station has a data receiving unit that extracts the transmitting station data from the echo.

In a fifth bistatic radar system according to the present invention, in the fourth system, the modulating section performs phase modulation on the search radio wave in accordance with the value of each digit of an N-ary code (N ≧ 2). It is characterized by the following.

In a sixth bistatic radar system according to the present invention, in the fifth system, the modulating section performs chirp modulation for each section of the search radio wave corresponding to each digit of the N-ary code. Features.

In a seventh bistatic radar system according to the present invention, in the above-mentioned fourth system, the modulating section may be arranged so that the modulating section performs the search radio waves in different frequency sweeping directions depending on the value of each bit of the binary code. Is chirp-modulated.

In a seventh bistatic radar system according to the present invention, in the above-mentioned fourth system, the transmitting station data is a binary code, and the modulating unit converts the binary code for each bit of the binary code. The search radio wave is chirp-modulated in different frequency sweep directions according to the value.

An eighth bistatic radar system according to the present invention is the bistatic radar system according to the fourth system, wherein the modulating section performs chirp modulation in which the amount of phase rotation differs for each digit of the N-ary code according to the value of the digit. And modulates the search radio wave.

According to an eighth bistatic radar system according to the present invention, in the fourth to seventh systems,
The transmitting station is a CW radar, and the modulating section continuously modulates by dividing the continuous search radio wave and continuously transmits each bit of the binary code.

According to a ninth bistatic radar system according to the present invention, in the fourth to eighth systems,
The transmitting station is a CW radar, and the modulating section continuously modulates by dividing the continuous search radio wave, and continuously transmits each digit of a code constituting the transmitting station data. Things.

In a tenth bistatic radar system according to the present invention, in the fourth to eighth systems, the transmitting station is a pulse radar, and the modulating unit is
A code constituting the transmission station data is sequentially associated with each pulse constituting the search radio wave one digit at a time.

In an eleventh bistatic radar system according to the present invention, at least one of the transmitting station and the receiving station is arranged on a mobile body, and the receiving station receives a direct wave of a search radio wave from the transmitting station. An echo delay time measuring unit that detects an echo delay time from when the echo is received, a radar transmitting / receiving unit used to detect the transmitting station, and the transmitting station based on a detection result of the radar transmitting / receiving unit. And a transmitting station position calculating unit for obtaining a positional relationship between the transmitting station and the own station, and a target position calculating unit for calculating the position of the target based on the positional relationship between the transmitting station and the local station, the echo delay time, and the echo receiving direction. And a part.

In a twelfth bistatic radar system according to the present invention, in the eleventh system, the radar transmitting / receiving unit has a function as a radar receiver for receiving a direct wave and an echo of the search radio wave. Features.

A thirteenth bistatic radar system according to the present invention, in the eleventh system, wherein the radar transmitting / receiving unit is provided separately from the primary radar for receiving the direct wave and the echo of the search radio wave. A surveillance radar, wherein the transmitting station includes a transponder that returns a response signal wave when receiving an interrogation signal wave from the secondary surveillance radar.

In a fourteenth bistatic radar system according to the present invention, at least one of the transmitting station and the receiving station is movable, and the receiving station is configured to receive a direct wave of a search radio wave from the transmitting station. An azimuth detecting unit for detecting an echo, an echo delay time measuring unit for detecting an echo delay time from when the direct wave is received until the echo is received, and a laser beam is emitted toward the receiving azimuth; A distance measuring unit that measures a distance to the transmitting station, a positional relationship between the transmitting station and the own station determined by the distance to the transmitting station measured by the distance measuring unit and the receiving direction, the echo delay time, and an echo. A target position calculating unit that calculates the position of the target based on a reception direction.

A fifteenth bistatic radar system according to the present invention has a transmitting station that emits an interrogation radio wave, and a receiving station that receives a response radio wave from a target and detects a position of the target. At least one of the transmitting station or the receiving station is located on a mobile, the transmitting station,
The receiving station has a transponder that responds to an interrogation radio wave transmitted from the reception station, and the reception station receives the interrogation radio wave from the transmission station directly and the reception time of the response radio wave from the target. A receiving time difference measuring unit for detecting the difference, and transmitting an interrogation radio wave to the transmitting station,
A radar transmitting / receiving unit that receives a response radio wave from the transmitting station and detects a position of the transmitting station; and a transmitting station position that obtains a positional relationship between the transmitting station and the own station based on a detection result of the radar transmitting / receiving unit. A calculation unit, and a target position calculation unit that calculates a position of the target based on a positional relationship between the transmitting station and the own station, the reception time difference, and a reception direction of the response radio wave from the target. It is characterized by the following.

A sixteenth bistatic radar system according to the present invention has a transmitting station for emitting interrogation radio waves, and a receiving station for receiving response radio waves from a target and detecting the position of the target. At least one of a transmitting station or the receiving station is arranged on a mobile body, the transmitting station has a transponder that responds to a secondary monitoring radar interrogation radio wave transmitted by the receiving station, and the receiving station includes: A reception time difference measuring unit that detects a reception time difference between a time at which the interrogation radio wave is directly received from the transmission station and a reception time of the response radio wave from the target, and transmits an interrogation radio wave to the transmission station; A secondary monitoring radar unit that receives a response radio wave from the transmitting station and detects a position of the transmitting station, and determines a positional relationship between the transmitting station and the own station based on a detection result of the secondary monitoring radar unit. Desired transmitting station position And a target position calculating unit that calculates the position of the target based on the positional relationship between the transmitting station and the own station, the reception time difference, and the reception direction of the response radio wave from the target. It is characterized by the following.

[0026]

[First Embodiment] Next, an embodiment of the present invention will be described with reference to the drawings. FIG.
FIG. 1 is a schematic configuration diagram of a bistatic radar system according to a first embodiment of the present invention.

The present system includes a transmitting station 10, a receiving station 12, and an information center 14. The transmitting station 10 has the same configuration as the conventional one, and has a radar transmitting unit 2 including an antenna.
0, a clock 22, while the receiving station 12 has a radar receiving unit 24 including an antenna, a clock 26
Is provided.

A case where the transmitting station 10 and the receiving station 12 of the present system are respectively arranged on a mobile body will be described.
Their positional relationship can change over time. Therefore, the transmitting station 10 and the receiving station 12 include self-position detecting units 30 and 32 for detecting the positions of the own stations, respectively. The self-position detecting units 30 and 32 are, for example, GPS (Global Positioning System).
m: Satellite navigation system) Receiver. In addition, as a self-position detecting unit, a conventionally known inertial navigation device (IN
S: inertial navigation system, and various radio navigation systems such as Loran and Omega.

Further, in the present system, similarly to the conventional bistatic radar, the position of the target where an echo is generated is made using the delay time between the transmission timing of the radar pulse from the transmitting station 10 and the echo receiving timing at the receiving station 12. Observe Therefore, the receiving station 12 needs to be able to accurately grasp the delay time of transmission and reception of the radar pulse, that is, the receiving station 12 needs to be able to know not only the time of its own station but also the accurate time of the clock 22 of the transmitting station 10. . From this request, the clock 22 of the transmitting station 10 and the clock 26 of the receiving station 12 are configured to keep the time synchronization. Specifically, for example, an atomic clock whose time is set mutually is used as the clock 22 and the clock 26. When GPS is used as the self-position detecting units 30 and 32, time information from GPS satellites can be used as the clocks 22 and 26.

The transmitting station 10 and the information center 14, and the information center 14 and the receiving station 12 are connected to the radio communication lines 34 and 3 respectively.
6 is connected. The transmitting station 10 has a data transmitting unit 38, and the data transmitting unit 38 transmits the transmitting station data obtained by the own station to the information center 14 via the communication line 34. As the transmission station data, information on the movement position of the own station detected by the self-position detection unit 30, information on the launch time of the radar beam from the radar transmission unit 20, information on the antenna azimuth (azimuth and elevation), other transmission frequencies, radar Information such as the pulse period is transmitted. These transmission station information is basically transmitted to the information center 14 in advance prior to the actual transmission,
The information center 14 stores the transmission station data transmitted from the transmission station 10 in a storage device such as a magnetic disk. Receiving station 1
2 has a data receiving unit 40, and the data receiving unit 40
Is connected to the information center 14 via the communication line 36, and can acquire transmission station data held in the information center 14.

The receiving station 12 has a target position calculating section 42 for calculating the position of the target 46 based on the information obtained by the local station in the configuration of the present system. Target position calculator 4
2 is based on the position information of the transmitting station 10 obtained from the information center 14 by the data receiving unit 40 and the position information of the own station output from the self-position detecting unit 32, and the positional relationship between the transmitting station 10 and the own station, for example, It grasps in which direction and at which distance the transmitting station 10 is located around its own station. This transmitting station 1
In determining the positional relationship between 0 and the receiving station 12, the position of the transmitting station 10 at the timing when the transmitting station 10 transmits a certain radar beam 44 and the receiving station 12 receives the echo 48 from the target 46 of the radar beam. The position of the receiving station 12 at the determined timing is associated with and used for calculation.

The target position calculating section 42 can further obtain the antenna orientation of the radar transmitting section 20 at the timing of transmitting the radar beam from the transmitting station data, and can receive the radar reception at the receiving timing of the echo from the radar receiving section 24. The antenna orientation of the unit 24 can be obtained. Further, the target position calculation unit 42 determines the transmission timing of the radar beam obtained from the transmission station data and the radar reception unit 2.
4 based on the time difference between the reception timing of the received echo and the distance between the position of the transmitting station 10 at the timing at which the radar beam was transmitted and the target 46 and the position of the receiving station 12 at the timing at which the echo was received. It is possible to calculate the total distance between the position and the target 46, that is, the propagation path length of the radar radio wave.

The target position calculating unit 42 calculates the position of the target 46 using the positional relationship between the transmitting station and the own station, the transmitting antenna direction, the receiving antenna direction, and the propagation path length obtained in this manner. The calculation itself is the same as that of the conventional bistatic radar, and the transmitting station 10 and the receiving station 12
And the target object 46 geometrically specifies a triangle at the apex. The target position calculation unit 42 determines the intersection between the arrival direction of the echo 48 and the transmission direction of the radar beam 44 of the transmission station as the target. The position where the object 46 reflects the radar beam 44 is calculated.

In the above configuration, both the transmitting station 10 and the receiving station 12 are movable. For example, there is a case where they are mounted on a ship or an aircraft. However, the present invention can be implemented when at least one of the transmitting station 10 and the receiving station 12 is installed on a mobile body, in which case the configurations of the transmitting station 10 and the receiving station 12 are simplified. sell. Specifically, when only the receiving station 12 is movable and the transmitting station 10 is fixed, the transmitting station 10 does not need to measure every time as long as the position of the own station is initially set. Therefore, the self-position detecting unit 30 is not required. Also,
The communication line 34 may be a wired communication. Similarly, the transmitting station 10
When only the mobile station is movable and the receiving station 12 is fixed, the receiving station 12 does not need the self-position detecting unit 32, and the communication line 36 may be a wired communication.

[Second Embodiment] FIG. 2 is a schematic configuration diagram of a bistatic radar system according to a second embodiment of the present invention. In the figure, the same elements as those in the above embodiment are denoted by the same reference numerals, and the description is simplified.

This system includes a transmitting station 60 and a receiving station 62. In the following example, similarly to the above-described embodiment, a case will be described in which both the transmitting station 60 and the receiving station 62 are movable. However, the present invention is applicable to a case where either the transmitting station 60 or the receiving station 62 is movable. Is effective.

The transmitting station 60 includes a radar transmitting section 64, a self-position detecting section 30, a clock 22, and a data transmitting section 66. The receiving station 62 includes a radar receiving unit 68, a self-position detecting unit 32, a clock 26, a data receiving unit 70, and a target position calculating unit 42.

The transmitting station 60 has information on its moving position, information on the time of launch of the radar beam from the radar transmitting section 64, information on the antenna azimuth (azimuth and elevation), and other information such as the transmission frequency and the period of the radar pulse. The transmitting station data composed of information is transmitted by being superimposed on the radar beam 44 by the radar transmitting section 64. The radar beam 44 reflects off the target 46 and reaches the receiving station 62 as an echo 48. In the receiving station 62, the radar receiving section 68 detects the transmitting station data from the echo 48 and outputs it to the target position calculating section 42. The target position calculation unit 42 uses the transmission station data to detect the position of the target 46 as in the above-described embodiment.

FIG. 3 is a block diagram showing a schematic configuration of the transmitting station 60. The data transmission unit 66 is a data generation unit 8
0, an encoding unit 82 and a radar transmitting unit 64
Is a modulator 84, a controller 86, a high-stable high-frequency oscillator (C
OHO: Coherent Oscillator) 88, high power amplifier 9
0, a transmission antenna 92, and an antenna orientation detection unit 94.

FIG. 4 is a block diagram showing a schematic configuration of the receiving station 62. As shown in FIG. The radar receiving unit 68 includes the receiving antenna 1
00, an antenna direction detector 102, a detector 104, and a high-stable high-frequency oscillator (COHO) 106,
The data receiving unit 70 includes a data detecting unit 110 and a data decrypting unit 112.

Hereinafter, the operation of this embodiment will be described. In the transmitting station 60, the data transmitting section 66 transmits the transmitting station position information from the self-position detecting section 30, the time information from the clock 22, the radar beam transmission timing information from the control section 86, and the antenna direction from the antenna direction detecting section 94. Enter information,
The data generator 80 generates a transmitting station data record based on the input data. For example, the transmission station data record “transmits at a frequency f and a pulse period τ _P from time T.” “From time T on the origin θ ₀ , φ _{0 of the} direction, the angle change rate Δθ, Δφ or the period τ _θ , τ _φ , And information such as “the position of the transmitting station 60 measured at the time T” is stored together with, for example, a header indicating the information type.

The coding section 82 converts the transmission station data generated by the data generation section 80 into a binary code and outputs it to the modulation section 84 according to a transmission timing signal from the control section 86.

The modulating section 84 has a pulsing function of synchronizing with a transmission timing signal from the control section 86 and forming a pulse by dividing a high-frequency signal from the high-stable high-frequency oscillator 88 into a finite time length. It has a function of phase-modulating the pulse in accordance with the value of each bit of the binary code from the transmission unit 66. The pulse train phase-modulated by the modulator 84 is amplified by the high power amplifier 90 and emitted from the transmission antenna 92 as a radar beam 44. Note that the direction of the transmitting antenna 92 is determined by an antenna azimuth detecting unit 94.
And is passed to the data transmission unit 66 as described above,
Used.

FIG. 5 is a schematic diagram for explaining the modulation processing in the modulation section 84. FIG. 7A shows a high-stable high-frequency oscillator 88.
, Which is a high-frequency signal input from the
FIG. 3B shows a waveform of an output signal from the modulation unit 84. The modulation unit 84 has, for example, a fixed period,
A COHO wave is cut out at a fixed time width to generate a pulse 120, and the phase of the cut out pulse is modulated. In this phase modulation, for example, a pulse corresponding to a bit of a binary code value “0” output from the data transmission unit 66 keeps a high-frequency signal contained therein in phase with a COHO wave, while a value “1” is output. The pulse corresponding to the bit "" is modulated so that the high-frequency signal included in the pulse has a phase opposite to that of the COHO wave. In the figure, pulse 120-1 is kept in phase with COHO and represents a value "0", and pulses 120-2 and 120-3 are shifted in phase opposite to COHO and represent a value "1".

The receiving station 62 receives the echo 4 from the target 46.
8 is received by the receiving antenna 100, and using the COHO signal from the high-stable high-frequency oscillator 106, the detection unit 104 performs pulse detection and phase detection of the pulse. The result is input to the data receiving unit 70. In the data receiving unit 70, the data detecting unit 110 measures the reception time of the detected pulse using the clock 26. Also, the data detection unit 11
0 acquires a bit string constituting a transmitting station data record from the result of the phase detection. The binary (binary) data acquired by the data detection unit 110 is sent to the data decoding unit 112. The data decoding unit 112 analyzes the data record sent from the data detection unit 110, extracts the transmission station data 130 stored therein, and outputs it to the target position calculation unit 42. Further, non-binary information 132 output from the data detection unit 110, for example, information such as the echo reception time and the intensity of the reception pulse is also output to the target position calculation unit 42. Then, the target position calculating unit 42 detects the position of the target 46 using the transmission station data thus input.

As described above, the present system uses a plurality of pulses to represent a bit string constituting a transmission data record. When the transmitting station 60 controls the azimuth of the transmitting antenna 92 so as to track the target 46, the receiving station 62
Since the echo 48 can be received for a relatively long time, that is, the bit string can be continuously received, the upper limit on the number of bits constituting the transmission data record is moderate. On the other hand, in the case of detecting and observing an unspecified target 46 in all directions, the transmitting station 60 generally uses the transmitting antenna 9.
2 is rotated in the azimuth direction at a predetermined cycle. Therefore, the echo 48 from the specific target 46 becomes intermittent according to the rotational scanning of the transmission antenna 92. In other words, the duration of one echo 48 is relatively short, and the number of pulses included in the echo 48, that is, the number of bits, is reduced to, for example, about several tens of bits. In this case, the transmission data record is divided for each type, and each transmission data record is
Consideration is made as necessary so that reception is suppressed to about a bit and one data record is completed by one echo reception. This consideration is particularly effective when the data to be transmitted requires real-time properties and it is not desirable to acquire data from a plurality of echo receptions over a relatively long time. Data requiring real-time data (for example, transmitting station 60)
The data record containing the position) is repeatedly transmitted at a high frequency, and real-time data such as data that can estimate data at another time based on data at one time or data that is not changed or has little change in time. Consideration of reducing the transmission frequency of low data (such as antenna azimuth information, pulse period, and frequency) is also effective in efficiently transmitting transmission station data from the transmission station 60 to the reception station 62.

Alternatively, instead of modulating the transmission pulse 120 with a binary code, the bit tolerance may be expanded by making the transmission pulse 120 multi-phase. For example, if modulation is performed every 22.5 °, modulation can be performed using a hexadecimal code. Polyphase modulation is also employed in modems and facsimile machines and is easy to implement.

The present system is also useful if any one of the transmitting station 60 and the receiving station 62 is movable. In such a case, particularly in such a case, the transmitting station 60 and the
The configuration of the receiving station 62 can be simplified.

A specific usage mode in which both the transmitting station 60 and the receiving station 62 move is, for example, a case where the transmitting station 60 and the receiving station 62 are ships. Radar transmitters are larger and generally more expensive than receivers, so it is difficult or widespread to mount monostatic radars with transmitters and receivers on relatively small vessels. Is considered difficult. On the other hand, large ships already use monostatic radar for safe navigation and navigation. Under such circumstances, according to the present invention,
A large vessel is configured as the transmitting station 60, and a small vessel is equipped with a receiving station 62 that can be configured to be relatively small. The transmitting station 60 on a large ship is different from the conventional radar apparatus in that the radar beam 44 is modulated and the transmitting station data is superimposed, but the size and weight can be configured without much difference from the conventional radar apparatus. Since most of the components can use the conventional radar device, it is easy to configure the transmitting station 60 by modifying the conventional device. According to the present system configured in this manner, even a small ship can detect other ships around the own ship using the echo 48 of the radar beam 44 emitted from the large ship, For example, safe navigation is realized even when visible navigation is not ensured, such as in bad weather or at night. By the way, as in this example, the present system has a high density of navigating vessels, and in an area requiring sufficient attention for safe navigation, it is easy to obtain a vessel serving as the transmitting station 60 and easily function effectively. The practical effect is extremely large.

Next, in a specific usage mode in which the transmitting station 60 is a fixed station and the receiving station 62 is a mobile station, the transmitting station 60 is installed on a land along the coast as a so-called “radiowave lighthouse” and is mounted on a small ship. The receiving station 62 is installed to ensure the safety of small vessels navigating the bay and the coast.

[Third Embodiment] A schematic configuration of a bistatic radar system according to a third embodiment of the present invention is basically the same as the configuration shown in FIG. 2 for the second embodiment. The following description is given with reference to this.
However, since the internal configurations of the radar transmitting unit and the radar receiving unit are different between the present system and the system of the above embodiment, different codes are used to avoid confusion, and the radar transmitting unit 150 and the radar transmitting unit 150 are used in the following description of the present system. It is represented as a receiving unit 152. In addition, the same elements as those in the above embodiment are denoted by the same reference numerals, and the description is simplified.

FIG. 6 is a schematic block diagram of a transmitting station of the present system. The radar transmitting unit 150 includes a modulating unit 154,
The modulation section 84 has a chirp modulation function in addition to a phase modulation function corresponding to a bit value. That is, the modulation unit 15
4 chirp-modulates a pulse storing a phase-modulated COHO signal having a constant period. For example, a high-frequency signal included in a pulse is modulated into a chirp pulse whose frequency sweeping direction is a direction of decreasing the frequency.

FIG. 7 is a schematic block diagram of a receiving station of the present system. The detector 156 differs from the detector 104 in that it has a pulse compression function and can compress chirped pulses. The detection unit 156 includes the detection unit 104
Similarly to the above, the phase detection of the pulse is also performed, whereby the value of the bit constituting the transmission station data can be extracted. The extracted binary data is used in the same manner as in the second embodiment, and the position of the target 46 is detected.

According to the present system, the S / N ratio for pulse detection can be improved by using a chirped pulse as the pulse.

In the above-described system, the transmitting station inverts the phase of the pulse according to the binary data so that the transmitting station data is superimposed on the radar beam 44 and transmitted to the receiving station. As another method of superimposing the beam 44 on the beam 44, there is a method using the chirp modulation described above. In the method using the chirp modulation, the direction of the frequency sweep of the chirp modulation, that is, the modulation for decreasing the frequency and the modulation for increasing the frequency, according to whether the bit value of the binary data is “0” or “1”. Modulation is switched. At the receiving station, the detector has two types of filters for compressing chirp modulated pulses corresponding to the direction of chirp modulation, and the bit value represented by the pulse is detected depending on which filter outputs the compressed pulse. Is done.

Alternatively, a method in which the phase of the pulse 120 corresponding to the binary data is rotated by 180 ° and the chirp modulation is used in the same manner as in the above embodiment is also possible. That is, the direction of the frequency sweep of the chirp modulation is fixed, for example, in the direction of decreasing the frequency, and when the bit value of the binary data is “0”, it remains unchanged, while when the bit value of the binary data is “1”. May be a method of rotating the phase by 180 °.

[Fourth Embodiment] The schematic configuration of a bistatic radar system according to a fourth embodiment of the present invention is basically the same as that of the second embodiment shown in FIG. The following description is given with reference to this.
However, since the internal configurations of the radar transmitting unit and the radar receiving unit are different between the present system and the system of the above embodiment, different codes are used to avoid confusion, and the radar transmitting unit 170 and the radar This is represented as a receiving unit 172. In addition, the same elements as those in the above embodiment are denoted by the same reference numerals, and the description is simplified.

FIG. 8 is a schematic block diagram of a transmitting station of the present system. The radar transmitter 170 transmits a continuous wave (CW), that is, the transmitting station of the present system is a CW radar. The modulator 174 basically outputs the COHO signal continuously without dividing it into short pulses. Modulation unit 1
Numeral 74 designates, for example, a predetermined period of the continuous signal, and associates each period with a bit of binary data representing transmission station data, and inverts the phase according to the value of the bit, for example, as in the second embodiment. Modulation, modulation that further performs chirp modulation as in the third embodiment, and modulation that indicates a bit value in the frequency sweep direction of chirp modulation are performed. In this way, the bit string is stored in the continuous wave.

FIG. 9 is a schematic block diagram of a receiving station of the present system. The detection unit 156 basically includes the modulation unit 174
Are used in the above embodiment corresponding to the modulation method adopted in the above.

The configuration of the radar transmitting unit 170 for transmitting the radar beam 44 as a continuous wave is generally simpler than the configuration of the radar transmitting unit for pulsing. Therefore, this system has an advantage that the configuration of the radar transmission unit 170 can be simplified. Also, since the number of bits that can be transmitted in a predetermined time is larger than in the case of pulsing, the transmission efficiency of the transmission station data is high, and accordingly, a method of coding the transmission station data with high noise resistance using redundancy is adopted. There is also an advantage that it can be done.

In the present system, the transmitting station basically has no reception timing, so that the transmitting station itself loses its function as a monostatic radar.
Therefore, the transmitting station in this case functions as the above-described radio lighthouse.

[Fifth Embodiment] FIG. 10 is a schematic configuration diagram of a bistatic radar system according to a fifth embodiment of the present invention. In the figure, the same components as those in the above embodiment are denoted by the same reference numerals, and the description is simplified.

This system comprises a transmitting station 200 and a receiving station 20.
2 is included. The transmitting station 200 includes a radar transmitting section 20 including an antenna, while the receiving station 202 includes a radar transmitting / receiving section 210 including an antenna, an echo delay time measuring section 212, a transmitting station position calculating section 214, and a target position calculating section 2
16 is provided.

The transmitting station 200 and the receiving station 202 of the present system
Are arranged on the moving object, and the positional relationship between the two can change with time. In that case, the receiving station 202
Requires the receiving station 20 to specify the position of the target 46.
2 It is necessary to know the positional relationship between the own station and the transmitting station 200. In the above embodiment, the transmitting station 200 and the receiving station 202
Have self-position detecting units 30 and 32, respectively. On the other hand, the system according to the present
0, which is different from the above embodiment in that the receiving station 202 does not require a self-position detecting unit. In the receiving station 202 of the present system, the radar transmitting / receiving unit 210 emits a radar beam 220, and transmits the echo 22 from the transmitting station 200.
2 is detected. Based on the transmission and reception of this radar beam,
The transmitting station position calculator 214 calculates the relative position of the transmitting station 200 with respect to the own station.

The radar transmitting / receiving section 210 of the receiving station 202
Is the target 4 of the radar beam 44 emitted by the transmitting station 200.
6 and the signal that the radar beam 44 directly reaches the receiving station 202, ie, the direct wave 224. The echo delay time measuring unit 212 outputs the direct wave 2
The time from when 24 is received to when the corresponding echo 48 is received, that is, the echo delay time is measured. From the echo delay time, the difference between the path length of the beam emitted from the transmitting station 200 and reflected by the target 46 to reach the receiving station 202 and the distance between the transmitting station 200 and the receiving station 202 can be known. Further, the radar transmitting / receiving unit 21
0 outputs the direction in which the echo 48 was received.

The target position calculating section 216 includes a positional relationship between the transmitting station and the receiving station output from the transmitting station position calculating section 214, an echo delay time output from the echo delay time measuring section 212, and a radar transmitting / receiving section 210. The position of the target object 46 is calculated based on the echo receiving direction output from.

[Sixth Embodiment] FIG. 11 is a schematic configuration diagram of a bistatic radar system according to a sixth embodiment of the present invention. In the figure, the same components as those in the above embodiment are denoted by the same reference numerals, and the description is simplified.

This system comprises a transmitting station 250 and a receiving station 25.
2 is included. The transmitting station 250 includes a radar transmitting unit 20 including an antenna, a secondary surveillance radar (Secondary Surv.
The receiving station 252 includes a radar receiving unit 24 including an antenna, a secondary monitoring radar (SSR) 256, an echo delay time measuring unit 212, a transmitting station position calculating unit 258, and a target position. The calculation unit 216 is provided.

The transmitting station 250 and the receiving station 252 of the present system
Also, similarly to the above-described embodiment, each is arranged on the moving body, and therefore, the positional relationship between them can change with time.
In the system according to the fifth embodiment, the receiving station 202 detects the position of the transmitting station 200 with respect to its own station by using the radar transmitting / receiving unit 210 that is the primary radar. The position of the transmitting station 250 with respect to the own station is detected by using the secondary monitoring radar 256 provided in 252. The secondary surveillance radar 256 transmits a radar beam which is an interrogation signal radio wave 260. On the other hand, when the transponder 254 of the transmitting station 250 receives the interrogation signal radio wave 260, the response signal radio wave after a certain response delay time defined by the standard. 262 is returned to the secondary monitoring radar 256. The transmission station position calculation unit 258 subtracts the response delay time of the transponder 254 from the time from when the secondary monitoring radar 256 transmits the interrogation signal radio wave 260 to when the secondary monitoring radar 256 receives the response signal radio wave 262, and transmits based on the remaining time. Bureau 25
The distance between 0 and the own station is calculated, the direction of the transmitting station 250 is determined based on the transmission direction of the interrogation signal radio wave, and the positional relationship of the transmitting station to the own station is obtained.

The target position calculating section 216 includes a positional relation between the transmitting station and the receiving station output from the transmitting station position calculating section 258, an echo delay time output from the echo delay time measuring section 212, and a radar receiving section 24. The position of the target object 46 is calculated based on the echo receiving direction output from.

Incidentally, as the secondary surveillance radar, those used in the field of air traffic control can be used. 2
The interrogation signal radio wave 260 emitted by the secondary monitoring radar 256 only needs to reach the transponder 254, and unlike the primary radar, it is affected by the attenuation in the forward path as well as the power loss according to the reflectance in the return path and the reflectance at the reflector. Absent. Therefore, the output of the secondary surveillance radar 256 can be small, so that the secondary surveillance radar 256 can be configured to be small.
52 itself can be reduced in size. This is the transmitting station 25
0, or it is advantageous to arrange the receiving station 252 on a mobile such as an aircraft.

[Seventh Embodiment] FIG. 12 is a schematic configuration diagram of a bistatic radar system according to a seventh embodiment of the present invention. In the figure, the same components as those in the above embodiment are denoted by the same reference numerals, and the description is simplified.

This system comprises a transmitting station 200 and a receiving station 30
0. The transmitting station 200 includes a radar transmitting unit 20 including an antenna, and is similar to the transmitting station of the fifth embodiment. On the other hand, the receiving station 300 includes a radar receiving unit 24 including an antenna, an echo delay time measuring unit 21
2. It includes an azimuth detecting unit 302, a distance measuring unit 304, a transmitting station position calculating unit 258, and a target position calculating unit 216.

The transmitting station 200 and the receiving station 300 of the present system
Also, similarly to the above-described embodiment, each is arranged on the moving body, and therefore, the positional relationship between them can change with time.
In the system according to the fifth embodiment, the receiving station 202 detects the position of the transmitting station 200 with respect to its own station by using the radar transmitting / receiving unit 210 that is the primary radar. Direction detecting unit 30 provided in 300
2 detects the direction of arrival of the direct wave 224 from the transmitting station 200 and specifies the azimuth of the transmitting station 200, and the distance measuring unit 304 emits a laser beam 305 in that direction.
From the own station to the transmitting station 2 based on the laser light 306 reflected by the
Measure the distance to 00. As described above, in the present system, the positional relationship of the transmitting station 250 with respect to the receiving station 300 is based on the measurement results of the azimuth detecting unit 302 and the distance measuring unit 304 instead of the primary radar in the system of the fifth embodiment. It is obtained by the transmission station position calculation unit 258 using the above.

The target position calculating section 216 includes the azimuth detecting section 30
2 and the positional relationship between the transmitting station and the receiving station obtained by the distance measuring unit 304, the echo delay time output from the echo delay time measuring unit 212, and the echo receiving direction output from the radar transmitting and receiving unit 210. The position of the target 46 is calculated.

The azimuth detecting unit 302 includes the radar receiving unit 24
It is desirable to use a separate antenna that does not require mechanical scanning and that can specify the direction of arrival of radar radio waves in a short time. The basic circuit configuration of the receiver of the azimuth detecting unit 302 may be the same as the conventional one.

[Eighth Embodiment] FIG. 13 is a schematic configuration diagram of a bistatic radar system according to an eighth embodiment of the present invention. In the figure, the same components as those in the above embodiment are denoted by the same reference numerals, and the description is simplified.

This system comprises a transmitting station 350 and a receiving station 35.
When the interrogation radio wave of the secondary surveillance radar is received, the position of a target 353 such as an aircraft equipped with a transponder that emits a response radio wave is detected.

The transmitting station 350 includes a secondary monitoring radar transmitting section 354 including an antenna and a transponder 254, while the receiving station 352 includes a secondary monitoring radar section 3 including an antenna.
56, reception time difference measurement section 358, transmission station position calculation section 25
8. A target position calculation unit 216 is provided.

The transmitting station 350 and the receiving station 352 of the present system
Also, similarly to the above-described embodiment, each is arranged on the moving body, and therefore, the positional relationship between them can change with time.
In this case, the secondary monitoring radar unit 356 of the receiving station 352 determines the positional relationship between the receiving station 352 itself and the transmitting station 350 necessary for the receiving station 352 to specify the position of the target 353.
It is obtained by emitting the interrogation radio beam 370 of the next monitoring radar and detecting the response radio wave 372 from the transponder 254 of the transmitting station 350. That is, the transmitting station position calculating unit 258 transmits the interrogation radio wave of the secondary monitoring radar and the transmitting station 3 to the receiving station 352 based on the time from the transmission of the interrogating radio beam 370 to the reception of the response radio wave 372.
50 relative positions are calculated.

The secondary monitoring radar unit 35 of the receiving station 352
6 receives the interrogation radio beam 374 emitted from the transmitting station 350 using the secondary monitoring radar transmitting unit 354, and receives the target object 353.
Response wave 376 emitted by the transponder of
The interrogation beam emitted by 50 directly detects the signal that reaches the receiving station 352, that is, the direct wave 378.
The reception time difference measurement unit 358 measures a reception time difference between the time when the direct wave 378 is received and the time when the response radio wave 376 corresponding to the direct wave 378 is received. Based on the reception time difference, the difference between the distance between the transmitting station 350 and the receiving station 352 relative to the total distance of the distance from the transmitting station 350 to the target 353 and the distance from the target 353 to the receiving station 352 is known. be able to. Further, secondary monitoring radar section 356 outputs the direction in which response radio wave 376 has been received.

The target position calculating section 216 has a positional relationship between the transmitting station and the receiving station output from the transmitting station position calculating section 258, a receiving time difference output from the receiving time difference measuring section 358, and a secondary monitoring radar. The position of the target 353 is calculated based on the reception direction of the response radio wave output from the unit 356.

A commercial aircraft basically has a transponder of a secondary surveillance radar. Therefore, such a target 353 can be detected by the interrogation radio wave of the secondary monitoring radar and the response radio wave from the target 353 as in the present system. Thereby, the radar transmitting unit on the transmitting station 350 side can be a secondary monitoring radar whose output may be weaker than the primary radar, and the transmitting station 350 can be reduced in size and weight. Also, the receiving station 352 detects the position of the transmitting station 350 by using the secondary monitoring radar instead of the primary radar, so that the receiving station 352 can be reduced in size and weight. The transmitting station 350 and the receiving station 3
It becomes easy to mount 52 on a moving body.

[Ninth Embodiment] FIG. 14 is a schematic configuration diagram of a bistatic radar system according to a ninth embodiment of the present invention. In the figure, the same components as those in the above embodiment are denoted by the same reference numerals, and the description is simplified.

The present system comprises a transmitting station 400 and a receiving station 40
2 to detect the position of a target 403 such as an aircraft equipped with a transponder that emits a response radio wave when receiving an interrogation radio wave.

The transmitting station 400 includes a radar transmitting section 404 including an antenna and a transponder 406, while the receiving station 402 includes a radar transmitting / receiving section 408 including an antenna, a reception time difference measuring section 358, a transmitting station position calculating section 258, and a target position. The calculation unit 216 is provided. The radar transmitting / receiving unit 408 of the receiving station 402 emits an interrogation radio beam 420. The transponder 406 of the transmitting station 400 transmits a response radio wave 422 after receiving the interrogation radio beam 420 for a predetermined time, and the radar transmitting / receiving unit 408 detects the response radio wave 422.

The transmitting station 400 and the receiving station 402 of the present system
Also, similarly to the above-described embodiment, each is arranged on the moving body, and therefore, the positional relationship between them can change with time.
In this case, the positional relationship between the receiving station 402 itself and the transmitting station 400 required for the receiving station 402 to specify the position of the target 403 is determined by the radar transmitting / receiving unit 408 of the receiving station 402 and the transponder 406 of the transmitting station 400. Are detected based on the transmission and reception of the interrogation radio wave beam 420 and the response radio wave 422 between them. That is, the transmitting station position calculating unit 258 transmits the interrogation radio beam 420 when the response radio wave 422 is returned.
On the basis of the launch direction of the receiver station 4 and the time from the transmission of the interrogation radio beam 420 to the reception of the response radio wave 422.
The relative position of the transmitting station 400 with respect to O.2 is calculated.

The radar transmitting / receiving section 408 of the receiving station 402
Is a response radio wave 426 emitted by the transponder of the target object 403 in response to the interrogation radio beam 424 emitted by the transmitting station 400, and a signal that the interrogation radio beam emitted by the transmission station 400 directly reaches the receiving station 402, ie, a direct wave. 42
8 is detected. The reception time difference measurement unit 358 measures a reception time difference between the time when the direct wave 428 is received and the time when the response radio wave 426 corresponding to the direct wave 428 is received. Based on the reception time difference, the transmitting station 400
, And the difference between the distance between the transmitting station 400 and the receiving station 402 with respect to the total distance of the distance from the target 403 to the target station 403 and the distance from the target 403 to the receiving station 402.
Further, radar transmitting / receiving section 408 outputs the direction in which response radio wave 426 was received.

The target position calculating section 216 includes a positional relationship between the transmitting station and the receiving station output from the transmitting station position calculating section 258, a receiving time difference output from the receiving time difference measuring section 358, and a radar transmitting / receiving section 408. The position of the target object 403 is calculated based on the reception direction of the response radio wave output from.

The secondary surveillance radar used in the eighth embodiment has an international standard defined as an air traffic control radar. On the other hand, the present system uses the radar transmitting unit 404, the transponder 406, the radar transmitting / receiving unit 408, and the transponder of the target 403 as a transponder.
This shows that the system can be configured using a system other than the secondary surveillance radar of the international standard. For example, the specifications of the interrogation radio wave beam and the response radio wave used in the present system are not restricted by international standards, so that data is superimposed on them or the pulse is chirp-modulated as in the second to fourth embodiments. Can be freely adopted, and the S / N ratio can be improved by these methods. Further, since the radar wave reflection at the target 403 and the transmitting station 400 is not used, the transmitting station 400 and the receiving station 402 can be reduced in size and weight as in the eighth embodiment. It is possible to enjoy an advantage that the 402 can be easily mounted on a moving object.

[0091]

According to the first bistatic radar system of the present invention, the transmitting station detects its own position and the position of the own station toward the receiving station and the radar beam emission time. And a data transmitting unit that transmits the transmitting station data including, the receiving station, the positional relationship between the transmitting station and its own station, the time difference between the beam emitting time of the transmitting station and the echo receiving time at its own station, and By having a target position calculating unit that calculates the position of the target based on the echo receiving direction, a bistatic radar system in which the transmitting station is arranged on a mobile body can be configured, and the flexible setting of the radar coverage, Optimization is possible, and the effect of easy acquisition is obtained.

[0092] According to the second bistatic radar system of the present invention, the transmitting station has a data transmitting section for transmitting transmitting station data including its own position and beam launch time to the receiving station, The receiving station has a self-position detecting unit that detects the position of its own station, the positional relationship between the transmitting station and its own station, the time difference between the beam emitting time of the transmitting station and the echo receiving time at its own station, and the echo receiving direction. By having a target position calculation unit that calculates the position of a target based on it, it is possible to configure a bistatic radar system in which the receiving station is located on a mobile body, and it is possible to flexibly set and optimize radar coverage The effect that acquisition becomes easy is acquired.

According to the third bistatic radar system of the present invention, transmission station data from the transmission station to the reception station is transferred via the information center. Since the position of the information center is fixed, even if the transmitting station or the receiving station moves, there is an effect that the information center can be easily accessed from them. Further, the transmitting station and the receiving station are allowed to access the information center at a timing convenient for the own station. In other words, for example, when the transmitting station or the receiving station is on a mobile body, a situation may occur in which the transmitting station or the receiving station is temporarily unsuitable for data transmission / reception due to the situation of the moving destination or the like. Since there is no need to synchronize the transmitting station and the receiving station in data transfer,
Even in such a case, it is possible to obtain an effect that the transmission of the transmission station data is reliably performed.

[0094] According to the fourth bistatic radar system of the present invention, the data transmitting section has the modulating section for modulating the search radio wave in accordance with the transmitting station data coded in the multi-digit code, and the receiving station has the echo section. Since the transmission station data is superimposed on the radar beam and passed by having a data receiving unit that extracts the transmission station data from, the transmission station data does not require a separate communication line for passing, and the configuration is simple. There is an effect.

According to the fifth bistatic radar system of the present invention, in the fourth system, the method of modulating the search radio wave performs phase modulation according to the value of each digit of the multi-digit code. Accordingly, an effect that the modulation unit can be simply configured can be obtained.

According to the sixth bistatic radar system of the present invention, in the fifth system, the modulation method for the search radio wave performs chirp modulation for each section of the search radio wave corresponding to each digit of the multi-digit code. During reception, a compressed pulse is obtained, which has the effect of improving noise immunity in data transmission and reception.

According to the seventh bistatic radar system of the present invention, in the above-mentioned fourth system, the modulating section performs the search in a frequency sweep direction different for each bit of the binary code according to the value of the bit. The radio wave is chirp-modulated, and a compressed pulse is obtained at the time of reception, which also has the effect of improving noise immunity in data transmission and reception.

According to the eighth bistatic radar system of the present invention, in the above-mentioned fourth system, the modulating section comprises a chirp modulation system in which, for each digit of the N-ary code, the amount of phase rotation differs according to the value of the digit. This modulates the search radio wave and obtains a compressed pulse at the time of reception, which also has the effect of improving noise immunity in data transmission and reception.

According to the ninth bistatic radar system of the present invention, in the above fourth to eighth systems, the transmitting station is a CW radar, and the modulating section separates the continuous search radio wave to generate a continuous signal. By transmitting each digit of the multi-digit code continuously, the bit rate to be transmitted is improved, thereby shortening the transmission time of the transmission station data from the transmission station to the reception station, The effect is obtained that an encoding method having excellent noise characteristics can be adopted. Further, since it is not necessary to pulse the radar beam at the transmitting station, there is also an effect that a radar transmitting unit having a simple configuration can be used.

According to the tenth bistatic radar system of the present invention, in the above fourth to eighth systems, the transmitting station is a pulse radar, and each pulse constituting the search radio wave has a multi-ary code of 1 for each pulse. A modulation method that sequentially corresponds to each digit is employed. This modulation method is simpler than a modulation method in which one pulse includes a plurality of bits or an infinite number of bits, and the effect of simplifying the configuration of the modulation unit and the detection unit is obtained.

According to the eleventh bistatic radar system of the present invention, the receiving station detects the echo delay time from receiving the direct wave of the search radio wave from the transmitting station to receiving the echo. A time measuring unit, a radar transmitting / receiving unit used for detecting the transmitting station, a transmitting station position calculating unit for obtaining a positional relationship between the transmitting station and the own station based on the detection result of the radar transmitting / receiving unit, By having a target position calculating unit that calculates the position of the target based on the positional relationship with the station, the echo delay time, and the echo receiving azimuth, when the positional relationship between the transmitting station and the receiving station changes with time. Even if there is, the transmitting station and the receiving station can detect the position of the target without detecting the position of the own station, and without the transmitting station transmitting data such as the position of the own station to the receiving station. In other words, according to the present invention, even if the transmitting station and the receiving station are on a mobile body, there is no need for a means for detecting the position or a means for transferring data, which simplifies the system and reduces the time required for data transmission. There is an effect that reliability is improved by being released from the problem of errors.

According to the twelfth bistatic radar system according to the present invention, in the eleventh system, the radar transmitting / receiving unit in the receiving station has a function as a radar receiver for receiving a direct wave and an echo of the search radio wave. By having both, the effect of simplifying the configuration of the receiving station can be obtained.

According to the thirteenth bistatic radar system of the present invention, in the eleventh system, the radar transmitting / receiving unit in the receiving station is provided separately from the primary radar for receiving the direct wave and the echo of the search radio wave. The transmitting station is configured to have a transponder that returns a response signal wave when receiving an interrogation signal wave from the secondary monitoring radar. By using the secondary monitoring radar, the transmission output of the radar transmission / reception unit can be reduced, and the size and weight of the receiving station can be reduced.

According to the fourteenth bistatic radar system of the present invention, the receiving station detects an azimuth detecting section for detecting the receiving direction of the direct wave of the search radio wave from the transmitting station, and echoes the direct wave after receiving the direct wave. An echo delay time measuring unit that detects an echo delay time until receiving the signal, a distance measuring unit that emits laser light toward the receiving direction and measures the distance to the transmitting station, and a transmitting station measured by the distance measuring unit. The position relationship between the transmitting station and its own station, which is determined by the distance and the receiving direction, the echo delay time, and the target position calculating unit that calculates the position of the target based on the echo receiving direction. Even when the positional relationship with the station changes with time, the transmitting station and the receiving station do not detect the position of the own station, and the transmitting station transmits data such as the position of the own station to the receiving station. Also Ku, can detect the position of the target. In other words, according to the present invention, even if the transmitting station and the receiving station are on a mobile body, there is no need for a means for detecting the position or a means for transferring data, which simplifies the system and reduces the time required for data transmission. There is an effect that reliability is improved by being released from the problem of errors.

According to the fifteenth bistatic radar system of the present invention, there is provided a transmitting station for emitting an interrogation radio wave, and a receiving station for receiving a response radio wave from a target and detecting the position of the target. The transmitting station has a transponder that responds to an interrogation radio wave transmitted by the receiving station, and the receiving station receives the interrogation radio wave from the transmitting station directly and the reception time of the response radio wave from the target. A receiving time difference measuring unit for detecting a difference, a transmitter / receiver for transmitting an interrogation radio wave to the transmitting station, receiving a response radio wave from the transmitting station, and detecting a position of the transmitting station, and the radar transmitting / receiving unit A transmitting station position calculating unit for obtaining a positional relationship between the transmitting station and the own station based on the detection result of the transmitting station, and a positional relationship between the transmitting station and the own station, a reception time difference, and a receiving direction of a response radio wave from the target. Target By having a target position calculating unit that calculates the position, even if the positional relationship between the transmitting station and the receiving station changes with time, the transmitting station and the receiving station do not detect the position of their own station. Also, the transmitting station can detect the position of the target without transmitting data such as the position of the own station to the receiving station. In other words, according to the present invention, even if the transmitting station and the receiving station are on a mobile body, there is no need for a means for detecting the position or a means for transferring data, which simplifies the system and reduces errors in data transmission. Thus, there is an effect that reliability is improved by being released from the problem. In addition, since the target has a transponder, the reflected radio wave from the transmitting station to the target does not have to reach the receiving station, and the transmission output of the transmitting station can be reduced, and its small size and light weight can be achieved. Is achieved. Further, since the transmitting station also has a transponder in the radar in which the receiving station detects the position of the transmitting station, the transmission output can be reduced, and the size and weight of the receiving station can be reduced. These transmitting stations,
The size and weight of the receiving station can be reduced, so that they can be easily mounted on a mobile object.

According to the sixteenth bistatic radar system of the present invention, a transmitting station that emits interrogation radio waves,
A receiving station for receiving a response radio wave from the target and detecting the position of the target; a transmitting station having a transponder for responding to a secondary monitoring radar interrogation radio wave transmitted by the receiving station; Is a reception time difference measuring unit that detects a reception time difference between a time when an interrogation radio wave is directly received from the transmitting station and a reception time of the response radio wave from the target, and transmits an interrogation radio wave to the transmission station, and A secondary monitoring radar unit for receiving a response radio wave from the station and detecting the position of the transmitting station; and a transmitting station position for obtaining a positional relationship between the transmitting station and the own station based on the detection result of the secondary monitoring radar unit. A calculating unit and a target position calculating unit that calculates the position of the target based on the positional relationship between the transmitting station and the own station, the reception time difference, and the receiving direction of the response radio wave from the target, thereby transmitting the signal. The positional relationship between the station and the receiving station changes with time Even if the transmitting station, without each receiving station to detect the position of the mobile station, also without the transmitting station to transmit data such as the position of the own station to a receiving station,
The position of the target can be detected. That is, according to the present invention,
Even if the transmitting station and receiving station are on a mobile unit, there is no need for a means to detect their position or a means for data transfer, thereby simplifying the system and freeing up data transmission errors. This has the effect of improving reliability. In addition, since the target has a transponder, the reflected radio wave from the transmitting station to the target does not have to reach the receiving station, and the transmission output of the transmitting station can be reduced, and its small size and light weight can be achieved. Is achieved. Also,
Since the transmitting station also has a transponder in the radar in which the receiving station detects the position of the transmitting station, the transmission output can be reduced, and the size and weight of the receiving station can be reduced. By reducing the size and weight of the transmitting station and the receiving station, the effect of easily mounting them on a mobile body is obtained.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a bistatic radar system according to a first embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of a bistatic radar system according to a second embodiment of the present invention.

FIG. 3 is a schematic block diagram of a transmitting station according to a second embodiment of the present invention.

FIG. 4 is a schematic block diagram of a receiving station according to a second embodiment of the present invention.

FIG. 5 is a schematic diagram illustrating a modulation process in a modulation unit included in a radar transmission unit according to a second embodiment of the present invention.

FIG. 6 is a schematic block diagram of a transmitting station according to a third embodiment of the present invention.

FIG. 7 is a schematic block diagram of a receiving station according to a third embodiment of the present invention.

FIG. 8 is a schematic block diagram of a transmitting station according to a fourth embodiment of the present invention.

FIG. 9 is a schematic block diagram of a receiving station according to a fourth embodiment of the present invention.

FIG. 10 is a schematic configuration diagram of a bistatic radar system according to a fifth embodiment of the present invention.

FIG. 11 is a schematic configuration diagram of a bistatic radar system according to a sixth embodiment of the present invention.

FIG. 12 is a schematic configuration diagram of a bistatic radar system according to a seventh embodiment of the present invention.

FIG. 13 is a schematic configuration diagram of a bistatic radar system according to an eighth embodiment of the present invention.

FIG. 14 is a schematic configuration diagram of a bistatic radar system according to a ninth embodiment of the present invention.

FIG. 15 is a schematic configuration diagram of a conventional bistatic radar system.

[Explanation of symbols]

10, 60, 200, 250, 350, 400 transmitting station, 12, 62, 202, 252, 300, 352, 4
02 receiving station, 14 information center, 20, 64, 15
0, 170, 404 Radar transmitter, 22, 26 clock, 24, 68, 152, 172 Radar receiver, 3
0,32 self-position detection unit, 34,36 communication line, 3
8,66 data transmitter, 40,70 data receiver,
42,216 Target position calculator, 44 radar beam,
46,353,403 target, 48,222 echo, 80 data generator, 82 encoder, 84,15
4 Modulation unit, 86 Control unit, 88, 106 High stable high frequency oscillator, 90 High power amplifier, 92 transmitting antenna, 9
4,102 antenna azimuth detecting unit, 100 receiving antenna, 104,156 detecting unit, 110 data detecting unit,
112 data decoding unit, 120 pulses, 130 transmitting station data, 132 non-binary information, 210,408 radar transmitting / receiving unit, 212 echo delay time measuring unit, 21
4,258 Transmitting station position calculating unit, 224,378 direct wave, 254,406 transponder, 2562 monitoring radar, 260 interrogation signal radio wave, 262 response signal radio wave, 302 azimuth detecting unit, 304 distance measuring unit, 305
Distance measuring laser irradiation light, 306 Distance measuring laser reflected light, 35
4 Secondary monitoring radar transmitting section, 356 Secondary monitoring radar section, 358 reception time difference measuring section, 370, 374 Interrogation radio beam, 372, 376 Response radio wave.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-5-297125 (JP, A) JP-A-10-111350 (JP, A) JP-A-7-318639 (JP, A) JP-A-61-1986 173184 (JP, A) JP-A-9-26474 (JP, A) JP-A-6-148318 (JP, A) JP-A-3-273183 (JP, A) JP-A-3-655992 (JP, U) (58) Field surveyed (Int.Cl. ⁷ , DB name) G01S ⁷ /00-7/42 G01S 13/00-13/95

Claims (16)

(57) [Claims] 1. A bistatic radar system having a transmitting station that emits a search radio wave and a receiving station that detects an object based on an echo of the search radio wave, wherein the transmission station is arranged on a mobile body, and A self-position detecting unit that detects a moving position of a station, a synchronization with the time of the receiving station is maintained, a clock that measures an emission time of the search radio wave, and, toward the receiving station, the moving position and the moving position. A data transmitting unit for transmitting transmitting station data including a launch time, wherein the receiving station has a positional relationship between the transmitting station and its own station, a time difference between the launch time and the echo receiving time, and an echo receiving. A bistatic radar system, comprising: a target position calculating unit that calculates a position of the target based on a direction. 2. A bistatic radar system having a transmitting station that emits a search radio wave and a receiving station that detects a target object based on an echo of the search radio wave, wherein the transmitting station is configured to transmit the search radio simultaneously with the time of the receiving station. Is maintained, a clock that measures the launch time of the search radio wave, and a data transmitting unit that transmits, to the receiving station, transmitting station data that includes the launch time, wherein the receiving station comprises: A self-position detecting unit that is arranged on a mobile body and detects a moving position of the own station, based on a positional relationship between the transmitting station and the own station, a time difference between the launch time and the echo reception time, and an echo reception direction. A bistatic radar system, comprising: a target position calculating unit that calculates a position of the target. 3. The bistatic radar system according to claim 1, further comprising an information center interposed on a communication path of the transmission station data from the transmission station to the reception station, wherein the information center is Holding the transmission station data from the transmission station, and the reception station reads and acquires the transmission station data held in the information center. 4. The bistatic radar system according to claim 1, wherein the data transmission unit modulates the search radio wave according to the N-ary coded (N ≧ 2) transmission station data. A bimodal radar system, comprising: a modulating unit that modulates the data, and the receiving station includes a data receiving unit that extracts the transmitting station data from the echo. 5. The bistatic radar system according to claim 4, wherein the modulator modulates the phase of the search radio wave in accordance with the value of each digit of an N-ary code (N ≧ 2). Bistatic radar system. 6. The bistatic radar system according to claim 5, wherein the modulator performs chirp modulation for each section of the search radio wave corresponding to each digit of the N-ary code. Radar system. 7. The bistatic radar system according to claim 4, wherein the transmission station data is a binary code, and the modulation unit changes a frequency for each bit of the binary code according to a value of the bit. Chirp-modulating the search radio wave in a sweep direction. 8. The bistatic radar system according to claim 4, wherein the modulator modulates the search radio wave by chirp modulation having a different phase rotation amount according to a value of each digit of the N-ary code. A bistatic radar system. 9. The bistatic radar system according to claim 4, wherein the transmitting station is a CW radar, and wherein the modulating section continuously divides the search radio wave. Modulating and transmitting each digit of a code constituting said transmission station data continuously. 10. The bistatic radar system according to claim 4, wherein the transmitting station is a pulse radar, and the modulating unit is configured to generate the search radio wave with respect to each pulse. A bistatic radar system, wherein codes constituting transmitting station data are sequentially associated with one digit at a time. 11. A bistatic radar system having a transmitting station that emits a search radio wave and a receiving station that detects an object based on an echo of the search radio wave, wherein at least one of the transmission station and the reception station is mobile. An echo delay time measuring unit disposed on a body, wherein the receiving station detects an echo delay time from receiving a direct wave of the search radio wave from the transmitting station to receiving the echo. A radar transmitting / receiving unit used for detecting the position of the transmitting station, a transmitting station position calculating unit for calculating a positional relationship between the transmitting station and the own station based on a detection result of the radar transmitting / receiving unit, and a position of the transmitting station and the own station. Relationship, the echo delay time,
And a target position calculating unit that calculates the position of the target based on an echo receiving direction. 12. The bistatic radar according to claim 11, wherein the radar transmission / reception unit has a function as a radar receiver that receives a direct wave and an echo of the search radio wave. system. 13. The bistatic radar system according to claim 11, wherein the radar transmitting / receiving unit is a secondary monitoring radar provided separately from a primary radar that receives a direct wave and an echo of the search radio wave, and The station comprises a transponder that returns a response signal wave when receiving an interrogation signal wave from the secondary surveillance radar, wherein the station has a transponder. 14. A bistatic radar system having a transmitting station that emits a search radio wave and a receiving station that detects an object based on an echo of the search radio wave, wherein at least one of the transmitting station and the receiving station is mobile. It is possible that the receiving station comprises: an azimuth detecting unit for detecting a receiving azimuth of a direct wave of the search radio wave from the transmitting station; and an echo delay time from receiving the direct wave to receiving the echo. An echo delay time measuring unit that detects the distance, a laser beam is emitted toward the receiving direction, a distance measuring unit that measures a distance to the transmitting station, and a distance to the transmitting station measured by the distance measuring unit. A target position calculating unit that calculates the position of the target based on the positional relationship between the transmitting station and the own station determined by the receiving direction, the echo delay time, and the echo receiving direction. A bistatic radar system, comprising: 15. A bistatic radar system for detecting a position of a target equipped with a transponder that emits a response radio wave after a predetermined time when receiving an interrogation radio wave, comprising: a transmitting station that emits the interrogation radio wave; And a receiving station for detecting the position of the target object, wherein at least one of the transmitting station and the receiving station is arranged on a mobile object, and the transmitting station is the receiving station Has a transponder that responds to an interrogation radio wave transmitted by the reception station, and the receiving station detects a reception time difference between a time at which the interrogation radio wave is directly received from the transmission station and a reception time of the response radio wave from the target. A transmission time interrogation unit that transmits an interrogation radio wave to the transmitting station, receives a response radio wave from the transmitting station, and detects a position of the transmitting station. A radar transmitting / receiving unit, a transmitting station position calculating unit that determines a positional relationship between the transmitting station and the own station based on a detection result of the radar transmitting / receiving unit, a positional relationship between the transmitting station and the own station, the reception time difference, And a target position calculating unit that calculates a position of the target based on a reception direction of the response radio wave from the target. 16. A bistatic radar system for detecting a position of a target equipped with a transponder which emits a response radio wave after a predetermined time when receiving an interrogation radio wave of a secondary monitoring radar, comprising: a transmitting station which emits the interrogation radio wave; A receiving station that receives a response radio wave from the target and detects the position of the target, and at least one of the transmitting station and the receiving station is arranged on a mobile body, and the transmitting station Has a transponder responding to a secondary monitoring radar interrogation radio wave transmitted by the receiving station, the reception station includes: a time when the interrogation radio wave is directly received from the transmission station; and a response radio wave from the target object. A reception time difference measurement unit that detects a reception time difference from the reception time of the transmission time, an interrogation radio wave is transmitted to the transmission station, a response radio wave from the transmission station is received, and the position of the transmission station is detected. A secondary monitoring radar unit to be detected; a transmitting station position calculating unit for obtaining a positional relationship between the transmitting station and the own station based on a detection result of the secondary monitoring radar unit; a positional relationship between the transmitting station and the own station A target position calculating unit that calculates a position of the target based on the reception time difference and a reception direction of the response radio wave from the target.