RU2092902C1 - Method for detection of position of vehicle and device which implements said method - Google Patents

Abstract

FIELD: radio engineering, in particular, security devices for cars, railway equipment and other vehicles subjected to stealing, accidents, wrong destination and other emergency conditions. SUBSTANCE: method involves emission of noise-like wide-band signals from reference nodes. Superposition of signals in network of reference nodes provides navigation field in monitored region. Said wide-band signals are encoded and transmitted back by vehicle when error signal or external request are detected. Returned signals are received by reference nodes which measure time intervals between moments of emission of corresponding wide-band signal and receiving of returned signal. Reference nodes also generate information signal which contains data about decoded code of vehicle, value of measured time interval and position of reference node. This information signal is transmitted to central node which uses signals from at least two reference nodes for detection of position of vehicle. Position of vehicle is detected for large distance in network operation region. Such network may be developed using stationary and mobile self-detecting units (including cars, planes and satellites). Coordinates of all wanted vehicles may be detected in real-time mode. EFFECT: decreased cost for searching stolen or lost vehicles, increased efficiency of traffic control and crime protection. 2 cl, 5 dwg

Description

The invention relates to techniques for determining the location of a vehicle in an emergency, for example, when conditions arise that cause the appearance of alarms, and can be used to solve problems:
location of stolen cars;
traffic control, in particular identifying the location of cars in an emergency, as well as cars breaking away from the pursuit (or external surveillance) that violated the speed limit, etc.

 control the location of railway cars, for example, lost as a result of errors in the formation of trains.

A known method of protecting a car from theft, in which they generate an alarm in case of trying to open the door or start the engine and transmit this alarm to the central station [1]
The disadvantage of this method is the uncertainty of the location of the car stolen by attacking the driver or using means of transportation (transportation or towing) of the car.

A known method of preventing collisions with an alarm, which can be transmitted over the air to a central station [2]
The disadvantage of this technical solution is that the a priori uncertainty of the location of the car, caught in an emergency, cannot be reduced by the proposed tool.

 There is a method of protecting a car from theft [3] consisting in the fact that they carry out ultrasonic scanning inside the guarded car, generate an alarm when moving objects appear in the guarded object, and also when opening (or breaking) doors and windows, transmit this alarm signal over the air to the central station.

 The disadvantage of this method is the lack of protection against theft without hacking and penetration into the car at the parking place, for example, by taking the car on a platform out of the area with known coordinates.

 A known method for detecting and determining a vehicle’s location, based on approximation of the vehicle’s own magnetic field by a point dipole magnetic field [4], it is proposed to determine the direction of a vehicle’s motion relative to stationary points based on determining the components of the tensor of coordinate changes in magnetic induction (see IEEE Trans. 1975, V. MAG -11, N 2, 1977, V. AES-13, N 3).

 When implementing the proposed method using modern advances in superconducting magnetometry, the detection range of single moving cars will not exceed several hundred meters.

The disadvantages of the known magnetometric method are:
short range;
low accuracy, as well as resolution and bandwidth;
the high cost and complexity of the equipment associated with the need to cool the overall units of the meters and the use of very complex methods for selecting the magnetic field of the detected dipole against the background of interfering magnetic fields.

A known method for determining the location of vehicles in which synchronized radio pulses with the same repetition frequency are emitted from strong points. One of the points with known coordinates is assigned as the leader. The vehicle receives these pulses and measures the time difference between receiving signals from the master and slave points. For each signal difference, the corresponding hyperbolic line of the vehicle’s position is determined, and the vehicle’s location by the intersection of these lines [5]
The disadvantages of this method:
the inability to determine the location of the car during abductions and in emergency situations;
obviously high cost of self-determination automotive equipment;
low accuracy (hundreds of meters) and noise immunity.

 The system that implements this method [5] contains transmitting equipment of reference points and receiving equipment of vehicles, and the equipment of reference points consists of a serially connected time standard, a synchronization device, a phase encoding device and a radio transmitter, and the vehicle equipment consists of an antenna device, an analog device signal processing, devices for analog-to-digital conversion, devices for digital signal processing and synchronization, control devices and indicators In this case, the antenna device is connected to the first input of the analog signal processing device, which is connected to the digital signal processing and synchronization device through the first input and output of the analog-to-digital conversion device, the first output of the digital processing device is connected to the input of the control and indication device, and the second the output of the digital processing and synchronization device is connected to the second inputs of the analog processing and analog-to-digital conversion devices, the output of the control and indication device and connected to the second input of the digital signal processing and synchronization device.

Closest to the proposed technical solution is a method for determining the location of a vehicle, which consists in the fact that from mobile (for example, located on artificial Earth satellites) or stationary points with known coordinates emit broadband (rangefinder) navigation signals containing the necessary service and command information, on the vehicle, according to the approximate location, choose a working network (constellation) of 3-4 strong points, search, capture and the verification (in frequency and phase) of the signals of the selected reference points, compress the broadband signals by the methods of correlation processing and determine the distance (or pseudorange) to the points with known coordinates, determine the location on the vehicle using range-finding algorithms [6]
The disadvantages of this method: the known method provides the location of the vehicle directly by the driver, however, in emergency situations (theft, accident, etc.) the coordinates of the vehicle are required by the appropriate ground service, therefore, the disadvantage of this method is the inability to remotely determine the coordinates or at least is unacceptable low range of such remote positioning; for covert control it is unacceptable to use complex equipment on a car, however, when implementing the known method, the possibility of simplifying the equipment is limited due to the need to solve the following apparatus-intensive tasks directly on the vehicle:
search and selection of a working network of strong points with known coordinates,
search and tracking of broadband signals of selected reference points,
location calculation.

 Thus, the main disadvantage of this method is its complexity.

 The closest in technical essence and the achieved effect is a system that implements this method [6] This system contains the equipment of the vehicle and the equipment of the reference point, and the equipment of the vehicle consists of an antenna device connected to the input of the receiver, which is connected to the first input of the selection system and signal processing, the output of this system through a range measuring device (pseudorange) is connected to the first input of the computing complex, the first output of the computing to The complex through the search and tracking device is connected to the second input of the signal selection and processing system, and the second output of the computer complex is connected to the display and control unit, the output of this block is connected to the second input of the computer complex; the equipment of the reference point contains a time standard connected in series, a navigation signal generating system, a pseudo noise coding system, and a transmitting device.

 The disadvantage of this system is its complexity, the low efficiency of determining the coordinates, as well as the impossibility of their remote determination.

 In FIG. 1 is a structural diagram of a system that implements the proposed method for determining the location of a vehicle, where 1 is a vehicle subsystem, 2 reference point subsystem, 3 is a central reference point subsystem, 4 response signal transmitting device, 5 request signal receiving device, 6 vehicle code generating device means, 7 alarm code generator, 8 broadband antenna, 9 optimal noise-like signal receiver, 10 vehicle code selector, 11 devices in the selection of codes, 12 a device for measuring time intervals, 13 a device for generating a message, 14 a transmission device for a data reference point, 15 a transmission device for a request signal, 16 a noise-like code generator, 17 a device for selecting alarm codes, 18 a receiving device for a data transmission channel, 19 a computing device , 20 control and indication device, 21 transmitting device of the central strong point, 22 receiving device of the strong point, 23 decoding device.

In FIG. 2 shows an example of a device for generating alarm codes for a vehicle 6, where 24 ₁ .24 _n-1 is a valve device, 25 ₁ .25 _{n-1 is an} encoding device (for example, a delay line with taps), 26 is an adder.

In FIG. Figure 3 shows examples of the implementation of devices for selecting codes 10, 11 and 17, where 27 ₁ .27 _N delay line with taps, 28 ₁ .28 _N selector "m of m" (cascade of matches), 29 ₁ .29 _N valve device (matching scheme ), 30 ₁ . 30 _N control device (trigger), 31 ₁ .31 _N delay device, 32 ₁ .32 _N delay line with taps, 33 ₁₁ 33 _Nn-1 valve device (cascade of matches), m _i number of pulses in the code of the ith vehicle (i = 1.N), N is the number of protected vehicles.

 In FIG. 4 shows an example of executing a request decoder 23, where 34 is a request code selector, 35 is a gate device, 36 is a delay line with taps, 37 is a cascade of matches.

In FIG. 5 is a timing diagram explaining the operation of the system, where S _{15 the} signal at the output of the transmitter 15, S _BX9 is the relay signal at the input of the receiver 9 (a superposition of time-unresolved complex radio pulses generated from S ₁₅ pulses when encoded in devices 6 and 7, and due to multipath propagation in urban areas, i.e., due to signal reflections by buildings and constructions, obstacles and diffraction of the diffraction m. p.), S ₉ to a signal output of the receiver 9 (a sequence of compressed pulses), S _10ij od alarm j-th to i-th vehicle-controlled, ie, at the i-th output of the selector 10, S _{12i the} signal at the output of the first pulse selector from the packet 12, S _{17j the} signal at the output of the j-th channel of the alarm code selector 17, Then the duration of the radio pulse, τ _o time resolution (τ _o > kτ _and \, k = 1,1.2), τ _{and the} duration of the compressed pulse, τ ₁ and τ ₂ the propagation time of the radio pulse to the vehicle and vice versa (τ ₁ = τ ₂ ), T _p the pulse repetition period [T _p ≅ sup (τ ₁ + τ ₂ )], T _{i the} duration of the code of the i-th vehicle.

 The system that implements the proposed method works as follows.

Each subsystem 2 emits broadband pseudo-noise (PN) radio pulses S ₁₅ (see Fig. 5). These pulses are received by all subsystems of vehicles 1 located in the coverage area of the reference point. Simultaneously with the emission of each pulse at the reference point, the time counters of the device 12 are started.

In standby mode, each radio pulse passing through devices 8 and 5 is supplemented by similar pulses in device 6, i.e. from each radio pulse a code group is formed that uniquely identifies a given vehicle. The minimum coding discrete must correspond to the condition τ _o ≥ 1.1 ... 2τ _and , (here τ _{and the} duration of the compressed radio pulse). In cases of occurrence of alarms from the respective sensors (anti-theft devices, vehicle rollover hazard warning sensors, collision avoidance alarm systems, etc.) can be used as alarm sensors, valves 24 of device 7 are opened, to which T alarms are received _j , and pulses delayed in the delay lines 25 are added to the radio burst code packet in accordance with the alarm codes.

 Pseudo-noise codes, for example, with the “no more than one match” property, can be used to ensure effective separation of these codes (in devices 10 and 12, see below) after compression and detection of radio pulses (see, for example, MB Sverdlik. discrete signals. M. Sov. radio, 1975).

 A superposition of radio pulses (generally unresolved) is emitted through devices 4 and 8. Similarly, the signals of all reference stations 2 located in the reception zone of the corresponding relay 1 are relayed. Each reference point 2 emits pseudo-noise (for example, phase-shifted) radio pulses in accordance with its PN code and / or its frequency letter. To implement a small-sized broadband automobile antenna 8, technical solutions can be used, considered, for example, in the review "Broadband small-sized antennas of the VHF range", Zabayrebna Radioelectronics, 1990, N 2, p. 54-60.

 In the interests of the difficulty of eliminating transceiver antennas 8, it is advisable to use several antennas disguised as external elements of the vehicle.

определяет дальность R_i до ретранслятора 1

где τ₁ и τ₂ задержки распространения импульса подсистемы 2 до ретранслятора 1 и обратно;
T_i длительность кода i-го транспортного средства;

оценка аппаратурных задержек распространения сигнала;
c скорость распространения радиоволн.Relayed radio pulses are received by device 9 (S in Fig. 5), in which each pulse is compressed with an intrapulse modulation corresponding to the code of the generator 16. These pulses can be compressed using a matched filter or a correlation receiver (see, for example, TIIER, 1983, t. 71, N 10, pp. 75-93; YD Shirman. Resolution and compression of signals. M. Sov. Radio, 1974). The output of the receiver 9 appears a sequence of allowed pulses. The code selector 10 provides the selection of pulses, the time intervals between which correspond to the codes of vehicles relaying the signals of this reference point. The pulse sequence at the corresponding output of the device 28 _i corresponds to the alarm code T _j on the i-th vehicle S _10ij . This sequence is fed to the inputs of pulse selectors 11 and 17. The first pulse of the packet S _10ij passes through the open valve device 29 _i and is fed to the input of the control device (trigger) 30 _i , which generates a signal (relayed) to lock the valve device 29 _i . The same pulse, having passed the delay line 31 _i (T _ass = T _p , here T _p the pulse repetition period of the transmitter 15), returns the device 30 _i to its original position, i.e. at the output of the trigger 30 _i , a signal is formed that opens the valve 29 _i . The first pulse extracted from the packet stops the count in the corresponding channel (counter) of the measuring device 12. The value of the measured interval

determines the range of R _i to the relay 1

where τ ₁ and τ _{2 the} propagation delay of the pulse of subsystem 2 to the relay 1 and vice versa;
T _{i the} duration of the code of the i-th vehicle;

estimation of hardware signal propagation delays;
c propagation speed of radio waves.

Alarm codes S _{17j are} selected in the corresponding channel of the device 17.

 In the device 13, a message is generated (informational signal frame) about the detected vehicles. Known signal frame selection methodologies can be used (see, for example, Network-based satellite radio navigation systems. M. Sov. Radio, 1982, pp. 118-121).

; т.о. L=L(M, X_м, Y_м, i, j, τ_i).To solve the problem of determining the location of the vehicle on the subsystem of the central strong point 3, the structural unit of the message - line L should contain: service information about the subsystem of the strong point 2, i.e. its M number and current coordinates (if the strong point is mobile); code of the i-th vehicle (uniquely identifying its number and attributes); the nature of the alarm (determined by the alarm code T _j ); delay value

; thus L = L (M, X _m , Y _m , i, j, τ _i ).

Message L on channel 14 18 is transmitted to the subsystem of the central reference point 3. In the computing device 19, the messages of two or more subsystems of the reference points 2 determine the current location of the i-th vehicle. The initial system of equations has the form
(X _i -X _om ) ² + (Y _i -Y _om ) ² = R _im ²
m is 1, 2, k; inf k = 2
where X _i and Y _{i are the} current coordinates of the i-th vehicle;
X _om , Y _om coordinates of the m-th subsystem of the reference point;
R _{im the} distance to the i-th vehicle, measured on the m-th subsystem of the reference point (R _{im is} uniquely determined by the estimate of the time interval between the moment of emission of the code and the reception of the relay signal, see above).

The initial system of equations allows you to determine the location of the i-th vehicle as the point of intersection of the Earth’s surface and rangefinding position surfaces (i.e., spheres of radii R _im ). The algorithm for solving the original system of equations can be based on finite and iterative methods. To resolve the ambiguity associated with the nonlinearity of the original system of equations, known methods based on:
prior information about the location of the vehicle,
redundant range measurements
comparing the obtained coordinates with the plan of roads (streets), etc.

The decoded message from the output of the device 18 and the coordinates X _i and Y _i arrive at the control and display device 20 (for example, a display), which is the output device of the proposed system. A system that implements the proposed method can operate in the search mode for vehicles at the request of the subsystem of the central reference point 3. In this case, the inquiry signal through the devices 20 → 21 → 22 is transmitted to all reference points, at each of which the broadband radio pulse of the transmitter 15 is transformed into code groups according to the requested codes. On the i-th repeater 1, the request decoder 23 selects the code of the i-th vehicle, while at the output of the device 37 (i.e., the matching circuit of the selector of the request code 34) a signal is generated (high potential), the gate valve 35, which passes the signal from output device 6 for relay. The further procedure for determining the location of the i-th (requested) vehicle by the relayed signal does not differ from the above.

 External design of the system that implements the proposed method showed that the subsystem of the vehicle (repeater) 1, it is advisable to carry out with a small-sized active transceiver antenna and with autonomous or combined power supply. To increase security, it is possible to covertly place several repeaters on a vehicle. It is advisable to place the network of stationary subsystems of support points 2 on high-rise buildings and structures (masts, pipes of thermal power plants, etc.). Mobile subsystems of reference points can be used, the location of which is controlled by a network of subsystems of stationary reference points or by signals from radio navigation systems (for example, such as Navstar or Glonass).

The expected characteristics of the system that implements the proposed method:
The range of the "vehicle reference point" radio line (ie, the radius of the zone of operation of a stationary reference point), km
in urban conditions 20
out of town 50-70
Error of ranging in urban conditions, m 30-35
Vehicle location error after information processing, m 15-40
The number of simultaneously detected vehicles in the coverage area of a strong point Almost unlimited (≥ 10 ⁵ )
The probability of non-separation of the signal upon arrival at the reference point 10 ⁴ unresolved in time relayed signals ≅ 10 ^-6
The advantage of the proposed method and system is that the proposed method provides a solution to the problem of automated external (at ranges of several tens of km) determining the location of all vehicles in any region equipped with a network of strong points, while operations on vehicles are so simplified that the implementation of transport equipment funds can be organized at any production of a radio engineering profile. Implementation of equipment of subsystems of strong points and subsystems of the central strong point is possible at medium-level radio engineering facilities.

 A new quality is the ability to quickly (in real time) determine at the central station the current coordinates of all vehicles in the controlled region that triggered the alarm sensors, as well as vehicles that are wanted (except for vehicles that are opaque to radio waves places).

 Implementation of the proposed method will reduce the cost of searching for stolen or lost vehicles, increase the efficiency of traffic control and the fight against offenses.

 According to data from publications in the scientific and technical literature, it can be expected that the proposed technical solution will be of interest to enterprises and organizations of the Russian Federation, USA, Canada, Japan, Germany and Australia.

Claims (2)

 1. The method of determining the location of the vehicle, which consists in the fact that broadband signals are emitted at the reference points, receive these signals on the vehicle and determine its location, characterized in that the broadband signals received on the vehicle are converted into code addresses and messages and re-emitted to the reference points at which the optimal reception of the emitted signals is carried out, the first pulse of the compressed broadband signal is isolated and the time intervals between at the moments of emission of broadband signals by the reference point and the moments of reception of signals re-emitted by the vehicle, address signals and vehicle message signals are extracted, signals about the value of the measured time interval, location of the reference point and vehicle messages are generated and this signals are transmitted to the central reference point, on which according to the received signals from the reference points determine the location of the vehicle.  2. A vehicle positioning system comprising a vehicle subsystem, including a serially connected broadband antenna and a request signal receiving device, a reference point subsystem including a noise-like signal generator, the output of which is connected to the first input of the request signal transmitting device, characterized in that in the subsystem the reference point, an optimal noise-like signal receiver and a transport medium code selector are connected in series device, a code selection device, a time interval measuring device, a message generating device, a transmitting device, a receiving device and an alarm code selection device, the inputs of which are combined with the inputs of the code selection device and connected to the outputs of the vehicle code selector, the output of the receiving device is connected to the second the input of the transmitter of the interrogation signal, the first input of which is combined with the input of the optimal receiver of the noise-like signal and the first input of the device from measuring time intervals, the outputs of the device for selecting codes are connected to the information inputs of the device for measuring time intervals, the outputs of which and the outputs of the device for selecting alarm codes are connected through the device for generating messages to the transmitting device, the device for generating the vehicle code and the driver for the alarm code are entered into the subsystem of the vehicle , a response signal transmitting device and a decoding device, the input of which and the input of the and the vehicle is connected to the output of the request signal device, the output of the vehicle code generating device is connected to the second input of the decoding device, the output of which is combined with the output of the alarm code generator and connected to the input of the response signal transmitting device, a central reference point containing the transmitting a device, a receiver of a data transmission channel, a computing device and a control and indication device, the first input of which is combined the input of the computing device and connected to the output of the receiving device of the data transmission channel, the output of the computing device is connected to the second input of the control and indication device, the output of which is connected to the input of the transmitting device, the broadband antenna of the vehicle is connected via radio channel to the transmitter of the request signal and the optimal receiver of a noise-like signal reference point, the receiving and transmitting devices of which are connected by radio channel, respectively, with the transmitting devices ohm and the receiver of the data channel of the central reference point.

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