JP2006345426A - Receiving device, receiving method, and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve deterioration in performance caused by increasing in circuit size and Doppler shift when performing mobile reception by a beam space array antenna, and when a selected channel is except for an ideal reception channel relating to the Doppler shift. <P>SOLUTION: In a constitution using a beam space array antenna shown in Fig.1, Doppler broadening of each beam is made to be approximately uniform in a received channel, thereby it is ideal for the mobile reception. On the other hand, when a selected channel is changed, the above mentioned ideal beam pattern is to be collapsed, and the performance is to be deteriorated because the Doppler broadening becomes large. The number of beams for receiving a radio wave in all directions is to be increased and the number of systems to be needed for a signal processing in following stages. In this case, a direction of each beam is to be moved by changing a core W of a space DFT in a beam forming unit 101 as shown in Fig.1. Consequently, the number of beams for receiving the radio wave in all directions can be prevented from being increased. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a technique for receiving a multi-beam formed by an antenna.

  In recent years, techniques for receiving terrestrial digital broadcasts while moving at high speed, such as on-vehicle reception, have been actively studied. Domestic terrestrial digital broadcasting employs OFDM (Orthogonal Frequency Division Multiplexing) in which transmission is performed using a number of orthogonal carriers. In a reception environment with high-speed movement, Doppler shift occurs, so OFDM orthogonality is lost, and degradation of reception quality due to inter-carrier interference (ICI) becomes a big problem.

As a conventional receiving apparatus that solves this problem, there is a configuration disclosed in the following non-patent document.
FIG. 17A is a diagram illustrating a configuration of a receiving device 1000 disclosed in non-patent literature. The receiving apparatus 1000 includes an array antenna 1001, a plurality of tuners 1002, a beam forming unit 1003, a plurality of FFT units 1004, and a beam combining unit 1005. FIG. 17B is a diagram showing the arrangement of the array antenna 1001. Each element of the array antenna 1001 is arranged on the roof of the car and arranged in a straight line in parallel with the traveling direction of the moving speed v of the car. In FIG. 17B, as an example, the number of elements is 8 and the element interval is d.

Hereinafter, the operation of the receiving apparatus 1000 will be described. Array antenna 1001 receives radio waves and converts them into electrical signals. As shown in FIG. 17 (b), if the number of incoming waves is L, the output signal of the antenna element #i is R _i , and the incident angle and complex amplitude of the k-th incoming wave are θ _k and α _k , respectively, R _i is It is expressed by the following formula.

R _i = Σ _(k = 1 to L ₎ α _k exp (-j2πd cosθ _k / λ), (i = 0,1, ..., 7)
... <Formula 0-1>
Here, λ is the wavelength of the selected channel.

Output signals R _{0 to} R ₇ of each antenna element are extracted by the tuner 1002 and only the channel selected by the user is extracted and output. Expression 0-1 is an expression that focuses only on the selected channel, and can be interpreted as an output of the tuner 1002.
The beam forming unit 1003 performs spatial DFT (Discrete Fourier Transform) on the output of the tuner 1002 to form eight beam outputs B _{0 to} B ₇ represented by the following equations. W ₈ is the core of the spatial DFT.

B _m = Σ _{(i = 0 to 7)} R _i exp (-j2πmi / 8)
= Σ _{(i = 0 to 7)} R _i W ₈ ^mi , (m = 0,1, ..., 7) ... <Equation 0-2>

W ₈ = exp (-j2π / 8) ... <Formula 0-3>

FIG. 18 shows the configuration of the beam forming unit 1003. The beam forming unit 1003 includes a plurality of complex adders 1011 and a plurality of rotation operators 1012. With this configuration, spatial DFT represented by Equations 0-2 and 0-4 is performed.

The eight beam outputs B _{0 to} B ₇ are respectively subjected to FFT by the FFT unit 1004 and converted into frequency axis signals F _{0 to} F ₇ . The beam combining unit 1005 performs maximum ratio combining of the frequency axis signals F _{0 to} F ₇ and outputs the result to the error correction unit.
Here, assuming that L = 1 and α = 1 in Equations 0-1 and 0-2, the beam outputs B _{0 to} B ₇ are expressed by the following equations.

B _m = Σ _{(i = 0 to 7)} exp [-j [(8d cosθ + mλ) πi / 4λ]], (m = 0,1, ..., 7)
... <Formula 0-4>
FIG. 19 shows beam patterns of beam outputs B _{0 to} B _{7 obtained} by converting Equation 0-5 into dB. In the figure, the traveling direction of the vehicle is θ = 0 °, and is 0 ° to 360 ° counterclockwise. Figure 19 (a)
This is the case when d = 3λ / 8. Each beam has a symmetrical shape with the traveling direction as an axis. For example, with respect to B ₆ peaks are 48.2 ° and 311.8 °, a cos48.2 ° = cos311.8 °.

The Doppler frequency fd with respect to the incident angle θ is expressed by the following equation.

fd = v cosθ / λ (Formula 0-5)

From Equation 0-5, the Doppler frequencies of θ = 48.2 ° and 311.8 ° are the same, and B ₆ has two peaks, but the respective Doppler shifts can be regarded as the same.
Wijesena et al. "Beam-Space Adaptive Array Antenna for Suppressing the Doppler Spread in OFDM Mobile Reception", IEICE TRANS. COMMUN., VOL.E87-B, NO.1, Jan. 2004

Although not described in non-patent literature, the beam pattern in FIG. 19 (a) has a feature that the beam width is wider as it is closer to the traveling direction. From Equation 0-5, the Doppler frequency fd is proportional to cos θ. The value change rate of cos θ is small near 0 °, and the value change rate increases as it approaches 90 °. If all the beam outputs B _{0 to} B ₇ have the same beam width, the Doppler spread of B ₀ having a peak of 90 ° becomes large. In the beam pattern shown in FIG. 19A, the beam width is proportional to cos θ, and the Doppler broadening of B _{0 to} B ₇ has a stochastic distribution. Due to this property, even if the power distribution of the L arriving waves is biased only to a certain beam, the Doppler spread is stochastically the same distribution regardless of the incident angle θ. From the above, it can be said that the beam pattern of FIG. 19A is ideal.

By the way, the non-patent document states that “Because the beam pattern depends on the wavelength, it is difficult to receive all channels of digital terrestrial broadcasting, and this is a future problem”. The beam pattern in FIG. 19B is for d = λ / 2. This corresponds to the case of receiving a channel whose wavelength is 3/4 times that of the channel received in FIG. In the beam pattern of FIG. 19B, there are peaks at θ = 0 ° and 180 ° with respect to the beam output B ₄ . From equation 0-5, fd = ± v / λ, and the Doppler broadening of B ₄ becomes large.

From the above, although non-patent literature is effective for reception of a single channel, there has been a problem that reception performance deteriorates for reception of a plurality of channels.
In addition, since the beam pattern of FIG. 19A covers all directions with 7 beams B _{0 to} B ₃ and B _{5 to} B ₇ , the FFT unit 1004 in the receiving apparatus 1000 of FIG. . On the other hand, in the beam pattern of FIG. 19 (b), eight beams B _{0 to} B ₇ are covered in all directions, so eight FFT units 1004 are required in the receiving apparatus 1000 of FIG. 17 (a).

  From the above, the non-patent literature has a problem that the circuit scale is increased when receiving a plurality of channels.

  In order to achieve the above object, the invention of claim 1 of the present application is a receiving device, wherein the element spacing of the array antenna is such that each beam has a symmetrical shape about the moving direction at a specific receiving frequency. And the beam width is determined to be narrower as it moves away from the moving direction in a direction perpendicular to the moving direction, and when the received frequency is the specific value, the spatial DFT (Discrete Fourier Fourier transform) is obtained for the received signal of each element of the array antenna. (Transform) is performed and divided into a plurality of beams, and when the received frequency is different from the specific value, the spatial DFT calculation is modified to be divided into a plurality of beams, and the direction of each beam is changed. It is characterized by comprising a part.

The invention of claim 2 of the present application is the receiving apparatus of claim 1, wherein the beam forming unit is configured such that the number of beams covering all directions is equal to or less than the number of beams covering all directions at the specific reception frequency. The spatial DFT operation is modified.
The invention of claim 3 of the present application is characterized in that, in the receiving apparatus of claim 1 or 2, the deformation of the spatial DFT calculation in the beam forming unit is a change of the nucleus W of the DFT.

According to a fourth aspect of the present invention, in the receiving apparatus according to the third aspect, the beam forming unit has a table storing a deformation pattern of the nucleus W of the DFT for each reception frequency, and the first-order deformation pattern is obtained from the table. It is a feature that the spatial DFT operation is read and modified.
The invention according to claim 5 of the present application is a receiving device, and includes an antenna group including one or more antennas that receive radio waves, and the antenna group, with a moving direction as an axis at a specific reception frequency. When each beam has a symmetric shape and the beam pattern is determined so that the beam width becomes narrower as it moves away from the moving direction at a right angle, and when the reception frequency is different from the specific value, In particular, the present invention is characterized by including a beam combining unit that combines the beams after performing processing based on a predetermined standard for a beam that does not have a symmetrical shape.

  According to a sixth aspect of the present invention, in the receiving device according to the fifth aspect, the antenna group is configured by an array antenna, and further, an operation is performed on a received signal of each element of the array antenna, and divided into a plurality of beams. An output beam forming unit is included, and the element spacing of the array antenna is determined so as to be the beam pattern at a specific reception frequency.

The invention of claim 7 of the present application is characterized in that, in the receiving apparatus of claim 5 or 6, the beam combining unit provides the predetermined reference according to the signal quality of each beam.
The invention according to claim 8 of the present application is the receiving apparatus according to claim 7, wherein the beam combiner is not used for combining the beam not having the symmetric shape regardless of the signal quality, or the weight is reduced. It is characterized by.

The invention according to claim 9 of the present application is the receiving apparatus according to claim 7, wherein the beam combining unit does not have the symmetric shape when the signal quality of the beam not having the symmetric shape is equal to or lower than a threshold value. The beam is not used for synthesis or has a low weight.
According to a tenth aspect of the present invention, in the receiving apparatus according to the seventh aspect, the beam combining unit includes a signal quality of the beam not having the symmetric shape and a total signal quality of the beam having the symmetric shape. In the case where the ratio or difference is less than or equal to a threshold value, the beam not having the symmetrical shape is not used for synthesis, or the weighting is lowered.

According to an eleventh aspect of the present invention, in the receiving device according to the seventh aspect, the beam combining unit does not have the symmetric shape when the total signal quality of the beam having the symmetric shape is equal to or greater than a threshold value. The beam is not used for synthesis or has a low weight.
The invention according to claim 12 of the present application is a receiving device, and includes an antenna group including one or more antennas that receive radio waves, and the antenna group, with a moving direction as an axis at a specific reception frequency. When each beam has a symmetric shape and the beam pattern is determined so that the beam width becomes narrower as it moves away from the moving direction at a right angle, and when the reception frequency is different from the specific value, In particular, the beam selection unit is configured to include a beam selection unit that selects one of the beams after performing processing based on a predetermined criterion for a beam that does not have a symmetric shape. is there.

  According to a thirteenth aspect of the present invention, in the receiving device according to the twelfth aspect, the antenna group is configured by an array antenna, and further, an operation is performed on a received signal of each element of the array antenna, and divided into a plurality of beams. An output beam forming unit is included, and the element spacing of the array antenna is determined so as to be the beam pattern at a specific reception frequency.

The invention of claim 14 of the present application is characterized in that, in the receiving apparatus of claim 12 or 13, the beam selecting section provides the predetermined reference according to the signal quality of each beam.
According to a fifteenth aspect of the present invention, in the receiver according to the fourteenth aspect, the beam selection unit does not select a beam that does not have the symmetric shape regardless of signal quality.

According to a sixteenth aspect of the present invention, in the receiving device according to the fourteenth aspect, the beam selecting unit may be configured to have the symmetrical shape even if the signal quality of the beam having no symmetrical shape is the maximum among all the beams. When the ratio or difference with the maximum signal quality among the beams having the above is less than or equal to the threshold value, the beam not having the symmetric shape is not selected.
The invention according to claim 17 of the present application is a receiving device, which includes an antenna group including one or more antennas that receive radio waves, and the antenna group, with a moving direction as an axis at a specific reception frequency. When each beam has a symmetrical shape and the beam pattern is determined so that the beam width becomes narrower as it moves away from the moving direction at a right angle, and the reception frequency is different from the specific value, A beam correcting unit that outputs a beam that does not have a symmetric shape by performing an operation with another beam, and the beam related to a beam that does not have a symmetric shape when the reception frequency is different from the specific value. It is characterized by including a beam combining unit that combines the beams after processing the output from the correcting unit based on a predetermined standard.

  The invention according to claim 18 of the present application is a receiving device, which includes an antenna group including one or more antennas that receive radio waves, and the antenna group, with a moving direction as an axis at a specific reception frequency. When each beam has a symmetrical shape and the beam pattern is determined so that the beam width becomes narrower as it moves away from the moving direction at a right angle, and the reception frequency is different from the specific value, A beam correcting unit that outputs a beam that does not have a symmetric shape by performing an operation with another beam, and the beam related to a beam that does not have a symmetric shape when the reception frequency is different from the specific value. It comprises a beam selection unit that selects one of the beams after processing the output from the correction unit based on a predetermined standard. .

  According to a nineteenth aspect of the present invention, in the receiving device according to the seventeenth or nineteenth aspect, the antenna group is configured by an array antenna, and further, an operation is performed on a received signal of each element of the array antenna to form a plurality of beams. It is configured to include a beam forming unit that outputs separately, and the element spacing of the array antenna is determined so as to be the beam pattern at a specific reception frequency.

According to a twentieth aspect of the present invention, in the receiving device according to any one of the seventeenth to nineteenth aspects, the calculation in the beam correcting unit is a subtraction of an adjacent beam from a beam not having the symmetric shape. It is characterized by this.
According to a twenty-first aspect of the present invention, in the receiving device according to any one of the seventeenth, nineteenth, and twentyth aspects, the beam combining unit is configured to perform the calculation according to the signal quality of the calculation result regarding the beam that does not have the symmetric shape. A predetermined reference is provided.

According to a twenty-second aspect of the present invention, in the receiving device according to any one of the eighteenth to twentieth aspects, the beam selection unit is configured to perform the predetermined operation according to the signal quality of the calculation result regarding the beam not having the symmetric shape. It is characterized by providing a reference.
According to a twenty-third aspect of the present invention, in the receiving device according to any one of the seventeenth to twenty-second aspects, the beam correction unit has a table storing information on beams not having the symmetric shape with respect to each reception frequency. And reading and processing the information from the table.

The invention of claim 24 of the present application is a receiving device, which is an array antenna that receives radio waves, an antenna control unit that outputs a control signal for turning on or off each element of the array antenna, and the array antenna. And a beam forming unit that performs an operation on the received signal of each of the elements and outputs the signal divided into a plurality of beams, and each element of the array antenna includes the control signal output from the antenna control unit Each on or off based on
The element spacing of the array antenna is such that each beam has a symmetric shape about the moving direction at a specific reception frequency and is perpendicular to the moving direction with respect to a predetermined pattern for turning on or off each of the elements. The antenna control unit generates and outputs the control signal on the basis of a predetermined reference when the beam width is determined to be narrowed with increasing distance from the direction and the reception frequency is different from the specific value. To do.

According to a twenty-fifth aspect of the present invention, in the receiver according to the twenty-fourth aspect, the predetermined reference of the antenna control unit is such that the interval between the elements to be turned on is the same as that when the reception frequency is the specific value. It is characterized by being.
The invention of claim 26 of the present application is a receiving device, which includes an array antenna that receives radio waves, an antenna control unit that outputs a control signal for moving each element of the array antenna, and each of the array antennas. The beam forming unit that performs an operation on the received signal of the element and outputs the signal divided into a plurality of beams, and each element of the array antenna has a symmetrical shape with respect to the moving direction at each reception frequency. And moving so as to satisfy the element spacing such that the beam width becomes narrower as it moves away from the moving direction in a direction perpendicular to the moving direction.

According to a twenty-seventh aspect of the present invention, in the receiving device according to the twenty-sixth aspect, the array antenna is disposed on a rail, and each element is movable on the rail.
The invention according to claim 28 of the present application is the receiving device according to any one of claims 7 to 11, 14 to 16, 21, and 22, wherein the signal quality is power, C / N, error rate, or reliability information. It is characterized by being.

The invention of claim 29 of the present application is the receiver according to any one of claims 5 to 12, 17, 19 to 21, and 23, wherein the beam combiner does not have the symmetrical shape with respect to each reception frequency. It has a table which memorize | stored the information regarding a beam, The said information is read from the said table, It processes, It is characterized by the above-mentioned.
The invention of claim 30 of the present application is the receiver according to any one of claims 12 to 17, 18 to 20, and 22 to 24, wherein the beam selector does not have the symmetrical shape with respect to each reception frequency. It has a table which memorize | stored the information regarding a beam, The said information is read from the said table, It processes, It is characterized by the above-mentioned.

The invention of claim 31 of the present application is the receiver according to any one of claims 24 to 27, wherein the antenna control unit has a table storing the control signal for each reception frequency, and the signal from the table is stored. Is read and processed.
The invention of claim 32 of the present application is that in the receiving device of any one of claims 6 to 11, 13 to 16, and 19 to 31, the calculation of the beam forming unit is a spatial DFT (Discrete Fourier Transform). It is a feature.

  The invention according to claim 33 of the present application is a receiving method, and an element interval between the array antenna for receiving radio waves and the array antenna has a shape in which each beam is symmetrical about a moving direction at a specific receiving frequency. And the beam width is determined to be narrower as it moves away from the moving direction in a direction perpendicular to the moving direction, and when the received frequency is the specific value, the spatial DFT (Discrete Fourier Fourier transform) is obtained for the received signal of each element of the array antenna. (Transform) is performed and divided into a plurality of beams, and when the received frequency is different from the specific value, the spatial DFT calculation is modified to be divided into a plurality of beams, and the direction of each beam is changed. It is characterized by comprising steps.

  The invention according to claim 34 of the present application is a program characterized by describing a signal processing procedure for executing the receiving method according to claim 33.

  According to the invention of claim 1, which achieves the above object, the element spacing of the array antenna is such that each beam has a symmetric shape with the moving direction as an axis at a specific reception frequency, and is separated from the moving direction in a perpendicular direction. If the received frequency is different from a specific value, the spatial DFT calculation is transformed into multiple beams and the direction of each beam is changed to change the reception of multiple channels. The beam pattern can be modified in

According to the invention of claim 2, which achieves the above object, the spatial DFT operation is modified so that the number of beams covering all directions is equal to or less than the number of beams covering all directions at a specific reception frequency. Therefore, it is possible to prevent an increase in circuit scale in receiving a plurality of channels.
According to the invention of claim 3, which achieves the above object, the beam pattern can be corrected in the reception of a plurality of channels by changing the nucleus W of the spatial DFT.

According to the invention of claim 4 which achieves the above object, the beam pattern can be corrected in the reception of a plurality of channels by performing a modification of the spatial DFT calculation using a table.
According to the invention of claim 5, which achieves the above object, each beam has a symmetric shape with the moving direction as an axis at a specific reception frequency, and is separated from the moving direction in a perpendicular direction by using an antenna group. When the beam pattern is determined so that the beam width becomes narrower and the received frequency is different from the specific value, processing is performed on the basis of a predetermined criterion for each beam, particularly a beam that does not have a symmetric shape. In addition, by combining the beams, it is possible to reduce the influence of Doppler spread in reception of a plurality of channels and prevent deterioration in reception performance.

  Further, according to the invention of claim 6, which achieves the above object, the element spacing of the array antenna has a symmetrical shape about the moving direction at a specific reception frequency, particularly using an array antenna, In addition, when the beam width is determined to become narrower as it moves away from the moving direction at a right angle, and the reception frequency is different from the specific value, a predetermined reference is made for each beam, particularly a beam that does not have a symmetric shape. By performing the processing based on the above and combining each beam, it is possible to reduce the influence of the Doppler spread in the reception of a plurality of channels and prevent the reception performance from being deteriorated.

According to the invention of claim 7, which achieves the above object, the influence of the Doppler spread is reduced in the reception of a plurality of channels by combining each beam by setting a predetermined reference according to the signal quality of each beam. , Reception performance deterioration can be prevented.
Further, according to the invention of claim 8 which achieves the above object, in particular, a beam having no symmetrical shape regardless of signal quality is not used for synthesis or is reduced in weighting, thereby reducing Doppler in reception of a plurality of channels. It is possible to reduce the influence of spreading and prevent reception performance deterioration.

  Further, according to the invention of claim 9, which achieves the above object, the beam not having a symmetric shape is not used for synthesis for a beam not having a symmetric shape, particularly when the signal quality of the beam not having a symmetric shape is not more than a threshold value. Lowering the weighting reduces the effect of Doppler broadening in multi-channel reception, and if the power is low unless a beam that does not have a symmetric shape is included, a beam that does not have a symmetric shape is also combined. By using, reception performance deterioration can be prevented.

  According to the invention of claim 10, which achieves the above object, the ratio or difference between the signal quality of a beam not having a symmetric shape and the sum of the signal qualities of beams having a symmetric shape is not more than a threshold value. In addition, beams that do not have a symmetric shape are not used for synthesis, or the weighting is reduced to reduce the effect of Doppler broadening in multi-channel reception, and beams that do not have a symmetric shape are not included. When the power is small, a beam that does not have a symmetrical shape is also used for combining, so that it is possible to prevent reception performance deterioration.

  According to the invention of claim 11 which achieves the above object, when the total signal quality of the beam having a symmetric shape is equal to or greater than a threshold value, the beam having no symmetric shape is not used for synthesis or weighted. To reduce the effect of Doppler broadening in multi-channel reception, and if the power is low unless a beam that does not have a symmetric shape is included, a beam that does not have a symmetric shape is also used for synthesis As a result, it is possible to prevent the reception performance from deteriorating.

  According to the invention of claim 12, which achieves the above object, each beam has a symmetrical shape with the moving direction as an axis at a specific reception frequency by using an antenna group, and is separated from the moving direction in a perpendicular direction. When the beam pattern is determined so that the beam width becomes narrower and the received frequency is different from the specific value, processing is performed on the basis of a predetermined criterion for each beam, particularly a beam that does not have a symmetric shape. In addition, by selecting one of the beams, it is possible to reduce the influence of Doppler spread in the reception of a plurality of channels, and to prevent reception performance deterioration.

  Further, according to the invention of claim 13 which achieves the above object, the element spacing of the array antenna has a symmetrical shape with the moving direction as an axis at a specific reception frequency, particularly using an array antenna, In addition, when the beam width is determined to become narrower as it moves away from the moving direction at a right angle, and the reception frequency is different from the specific value, a predetermined reference is made for each beam, particularly a beam that does not have a symmetric shape. After performing processing based on the above, by selecting one of the beams, it is possible to reduce the influence of Doppler spread in the reception of a plurality of channels and to prevent reception performance deterioration.

According to the invention of claim 14, which achieves the above object, the influence of Doppler broadening in the reception of a plurality of channels is obtained by providing a predetermined reference according to the signal quality of each beam and selecting one of the beams. To reduce reception performance degradation.
According to the invention of claim 15, which achieves the above object, the influence of Doppler broadening is reduced in the reception of a plurality of channels by not selecting a beam particularly for a beam which does not have a symmetric shape regardless of signal quality. , Reception performance deterioration can be prevented.

  According to the invention of claim 16, which achieves the above object, even if the signal quality of a beam not having a symmetrical shape is the maximum among all beams, the maximum signal quality of a beam having a symmetrical shape is the maximum. If the ratio or difference between and is less than or equal to the threshold, the beam that does not have a symmetric shape is not selected, thereby reducing the effect of Doppler broadening in multi-channel reception and the beam that does not have a symmetric shape is selected. Otherwise, when the power is low, the reception performance can be prevented from deteriorating by selecting a beam that does not have a symmetric shape.

  According to the invention of claim 17, which achieves the above object, each beam has a symmetrical shape with the moving direction as an axis at a specific reception frequency, and is separated from the moving direction in a perpendicular direction by using an antenna group. When the beam pattern is determined so that the beam width becomes narrower and the received frequency is different from the specific value, a calculation is performed on the non-symmetrical beam among the plurality of beams with other beams. The output from the beam correction unit for the beam that is output and does not have a symmetric shape is processed based on a predetermined standard, and then the respective beams are combined so that the Doppler spread is received in the reception of multiple channels. It is possible to reduce the influence and prevent the reception performance from deteriorating.

  According to the invention of claim 18, which achieves the above object, each beam has a symmetric shape with the moving direction as an axis at a specific reception frequency, and is separated from the moving direction at a right angle by using the antenna group. When the beam pattern is determined so that the beam width becomes narrower and the received frequency is different from the specific value, a calculation is performed on the non-symmetrical beam among the plurality of beams with other beams. A plurality of channels are received by selecting one of the beams after processing the output from the beam correction unit regarding the beam that is output and does not have a symmetric shape based on a predetermined criterion. In this case, it is possible to reduce the influence of Doppler spread and prevent the reception performance from deteriorating.

  Further, according to the invention of claim 19, which achieves the above object, particularly using an array antenna, the element spacing of the array antenna is such that each beam has a symmetrical shape around the moving direction at a specific reception frequency, In addition, when the beam width is determined to become narrower as it moves away from the moving direction at a right angle, and the reception frequency is different from the specific value, a predetermined reference is made for each beam, particularly a beam that does not have a symmetric shape. After performing processing based on the above, by combining each beam or selecting one of the beams, the influence of the Doppler spread is reduced in reception of a plurality of channels, and reception performance deterioration is prevented. be able to.

According to the invention of claim 20, which achieves the above object, the influence of the Doppler spread is reduced in the reception of a plurality of channels by subtracting the adjacent beam from the beam not having a symmetric shape, thereby preventing the reception performance from being deteriorated. can do.
According to the invention of claim 21, which achieves the above object, the influence of the Doppler spread is reduced in the reception of a plurality of channels, particularly by combining each beam by setting a predetermined reference according to the signal quality of each beam. , Reception performance deterioration can be prevented.

According to the invention of claim 22, which achieves the above object, the influence of the Doppler broadening in the reception of a plurality of channels is obtained by providing a predetermined reference according to the signal quality of each beam and selecting one of the beams. To reduce reception performance degradation.
According to the invention of claim 23 which achieves the above object, the influence of Doppler broadening is reduced in reception of a plurality of channels by performing a calculation with a beam other than a symmetrical beam using a table. Thus, it is possible to prevent the reception performance from deteriorating.

  According to the invention of claim 24 that achieves the above object, each element of the array antenna is turned on or off in a predetermined pattern for each reception frequency, so that each channel is received with a moving direction as an axis. The beam has a symmetrical shape and can generate an ideal beam pattern that narrows the beam width as it moves away from the moving direction at a right angle, reducing the effect of Doppler broadening when receiving multiple channels, and receiving performance Deterioration can be prevented.

  Further, according to the invention of claim 25 which achieves the above object, the direction of movement in reception of a plurality of channels is made by making the interval of the elements to be turned on for each reception frequency the same as in the case of generating an ideal beam pattern. Each beam has a symmetrical shape with respect to the axis, and an ideal beam pattern that narrows the beam width as it moves away from the moving direction at a right angle can be generated, reducing the effect of Doppler broadening in receiving multiple channels. Thus, it is possible to prevent the reception performance from being deteriorated.

  According to the invention of claim 26, which achieves the above object, each beam is symmetrical about the moving direction in reception of a plurality of channels by moving so as to satisfy each element spacing of the array antenna for each reception frequency. Can generate an ideal beam pattern that narrows the beam width as it moves away from the moving direction in a direction perpendicular to the moving direction, reducing the effect of Doppler broadening when receiving multiple channels, and preventing reception performance degradation can do.

  According to the invention of claim 27, which achieves the above object, each element is movable on the rail, whereby each beam has a symmetric shape with respect to the moving direction and moves in reception of a plurality of channels. It is possible to generate an ideal beam pattern in which the beam width becomes narrower with increasing distance from the direction, and the influence of Doppler broadening can be reduced in reception of a plurality of channels, and reception performance deterioration can be prevented.

  According to the invention of claim 28 which achieves the above object, a beam having no symmetrical shape is provided by providing a predetermined standard using power, C / N, error rate, or reliability information as signal quality. By performing beam combining after processing, or selecting one of the beams, it is possible to reduce the influence of Doppler broadening in reception of a plurality of channels and prevent reception performance deterioration. .

According to the invention of claim 29 which achieves the above object, by performing processing based on a predetermined standard for a beam having no symmetrical shape using a table, and combining each beam, In the reception of a plurality of channels, the influence of Doppler spread can be reduced and reception performance deterioration can be prevented.
According to the invention of claim 30, which achieves the above object, a beam having no symmetrical shape is processed using a table based on a predetermined criterion, and one of the beams is selected. By doing so, it is possible to reduce the influence of Doppler spread in reception of a plurality of channels, and to prevent reception performance deterioration.

  According to the invention of claim 31, which achieves the above object, by controlling each element of the array antenna using a table, each beam has a symmetrical shape about the moving direction in reception of a plurality of channels. In addition, an ideal beam pattern in which the beam width becomes narrower as it moves away from the moving direction in a direction perpendicular to the moving direction can be generated, and the influence of Doppler spread can be reduced in receiving a plurality of channels, thereby preventing reception performance deterioration.

According to the invention of claim 32 which achieves the above object, it can be divided into a plurality of beams by performing spatial DFT.
According to the invention of claim 33 that achieves the above object, the element spacing of the array antenna is such that each beam has a symmetric shape with the moving direction as an axis at a specific reception frequency, and is separated from the moving direction at a right angle. If the received frequency is different from the specific value, the spatial DFT calculation is transformed into a plurality of beams and the direction of each beam is changed by changing the direction of each beam. The beam pattern can be corrected in the reception.

  According to the invention of claim 34, it is possible to realize a program that describes a signal processing procedure for executing a receiving method.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
(Embodiment 1)
FIG. 1 is a diagram showing a configuration of receiving apparatus 100 according to Embodiment 1 of the present invention. The receiving apparatus 100 in FIG. 1 has a configuration in which the beam forming unit 101 is replaced as compared with the receiving apparatus 1000 in FIG.

Hereinafter, the operation of the receiving apparatus 100 will be described. The beam forming unit 101 knows which channel the user has selected based on the channel selection information, changes the core of the spatial DFT calculation, and outputs the calculation results B ₀ ^{′ to} B ₇ ^′ .
FIG. 2 (a) shows the configuration of the beam forming unit 101, and FIG. 2 (b) shows a beam pattern relating to the calculation results B ₀ ^{′ to} B ₇ ^′ when d = λ / 2. 2A, the beam forming unit 101 has a configuration in which a ROM table 111 is added as compared with the beam forming unit 1003 in FIG.

The ROM table 111 selects and outputs the core W of each rotation operator 1012 based on the channel selection information. That is, in the beam forming unit 1003 in FIG. 18, the core of each rotation operator is fixed regardless of the reception channel, whereas in FIG. 2A, the beam forming unit 101 has each rotation operator for each reception channel. Change the core of.
When the beam pattern of FIG. 2 (b) is seen, since all directions are covered with six beams B _{0 to} B ₅ , it is understood that the number of the FFT units 1004 in the receiving apparatus 100 of FIG. . Seven FFT units 1004 in the receiving apparatus 1000 in FIG. 17A are required when d = 3λ / 8, and six of them may be used in the present embodiment.

Next, FIG. 2A illustrates a method for designing the nucleus of each rotation operator in the beam forming unit 101. Assuming that d = 3λ / 8 and d = λ / 2 in Expression 0-5, the beam outputs B _{0 to} B ₇ are respectively expressed by the following expressions.

B _m (d = 3λ / 8) = Σ _{(i = 0 to 7)} exp [-j [(3cosθ + m) πi / 4]], (m = 0,1, ..., 7)
... <Formula 1-1>
B _m (d = λ / 2) = Σ _{(i = 0 to 7)} exp [-j [(4cosθ + m) πi / 4]], (m = 0,1, ..., 7)
... <Formula 1-2>
In Formula 1-1, when the following formula is satisfied, the phases of all elements i = 0 to 7 are aligned and become the maximum value.

(3cosθ + m) i / 4 = 2n, (n is an integer) ... <Equation 1-3>

From the expression 1-3, when the following expression is established, the beam outputs B _{0 to} B _{7 of the} expression 1-1 each have a maximum value (peak).

B ₀ : cos θ = 0, B ₁ : cos θ = -1/3, B ₂ : cos θ = -2/3, B ₃ : cos θ = -1,
B _{4: none, B 5: cosθ = 1,} B 6: cosθ = 2/3, B 7: cosθ = 1/3
... <Formula 1-4>
By modifying Equation 1-2 as follows, the peak distribution becomes the same as Equation 1-4 even when d = λ / 2.

B _m ^' (d = λ / 2) = Σ _{(i = 0 to 7)} exp [-j [(4cosθ + m) πi / 4]] exp (-jmπi / 12),
(m = 0,1, ..., 7) ... <Formula 1-5>

In this case, when the following equation holds, the beam outputs B _{0 to} B ₇ of d = λ / 2 have the maximum value (peak).

_{B 0: cosθ = 0, B} 1: cosθ = -1 / 3, B 2: cosθ = -2 / 3, B 3: cosθ = ± 1,
_{B 4: cosθ = 2/3, B} 5: cosθ = 1/3, B 6: cosθ = 0, B 7: cosθ = -1/3
... <Formula 1-6>

here,

exp (-jmπi / 12) = W ₂₄ ^mi ... <Formula 1-7>

Therefore, when the modification of Expression 1-5 is applied to Expression 0-2, the following expression is obtained.

B _m ^' (d = λ / 2) = Σ _{(i = 0 to 7)} R _i W ₈ ^mi W ₂₄ ^mi
= Σ _{(i = 0 to 7)} R _i W ₆ ^mi , (m = 0,1, ..., 7) ... <Equation 1-8>

From Equation 1-8, the nucleus W ₈ is changed to W ₆ .

  The ROM table 111 may store the core W of each rotation operator 1012 for each channel. Other operations are the same as those of the receiving apparatus 1000 in FIG. Therefore, when d = 3λ / 8, there is no asymmetric beam, and as a result, the receiving apparatus 100 performs exactly the same operation as the receiving apparatus 1000 in FIG. On the other hand, when d = λ / 2, there is an asymmetric beam, and the above control is performed.

With the above configuration, it is possible to prevent an increase in circuit scale even when receiving a plurality of channels.
(Embodiment 2)
FIG. 3 is a diagram showing a configuration of receiving apparatus 200 according to Embodiment 2 of the present invention. The receiving apparatus 200 of FIG. 3 has a configuration in which the beam combining unit 201 is replaced as compared with the receiving apparatus 1000 of FIG. FIG. 4 is a diagram illustrating a configuration of the beam combining unit 201. The beam combining unit 201 includes a combining unit 211, a power measuring unit 212, and a ROM table 213.

Hereinafter, the operation of the receiving apparatus 200 will be described. The beam combining unit 201 knows which channel the user has selected based on the channel selection information. The ROM table 213 outputs asymmetric beam information based on the channel selection information. The asymmetric beam information is information indicating whether each of the frequency axis signals F _{0 to} F ₇ is asymmetric with respect to the traveling direction of the vehicle. The ROM table 213 may store for each channel whether or not the beams F _{0 to} F ₇ are asymmetric.

The power measuring unit 212 calculates the powers of F _{0 to} F ₇ and outputs an asymmetric beam control signal based on the asymmetric beam information. The asymmetric beam control signal is information indicating whether or not an asymmetric beam is used for synthesis. The power measurement unit 212 generates an asymmetric beam control signal so that the asymmetric beam is not always used for synthesis.
Based on the asymmetric beam control signal, the synthesis unit 211 performs synthesis using only signals other than the asymmetric beam among the frequency axis signals F _{0 to} F ₇ , and outputs the synthesized signal to the error correction unit.

Other operations are the same as those of the receiving apparatus 1000 in FIG. Therefore, when d = 3λ / 8, there is no asymmetric beam, and as a result, the receiving apparatus 200 performs exactly the same operation as the receiving apparatus 1000 in FIG. On the other hand, when d = λ / 2, there is an asymmetric beam, and control regarding the asymmetric beam is performed as described above.
With the above configuration, it is possible to prevent the reception performance from being deteriorated without being affected by the Doppler spread by controlling the asymmetric beam not to be used for the synthesis even when receiving a plurality of channels.

The power measurement unit 212 may generate an asymmetric beam control signal as follows. If the power is small unless the asymmetric beam is included, the asymmetric beam can also be used for synthesis by the following configuration.
(1) When the power of the asymmetric beam is below the threshold, it is not used for synthesis.
(2) When the ratio or difference between the power of the asymmetric beam and the total power of the symmetric beam is equal to or less than the threshold value, it is not used for synthesis.

(3) When the total power of the symmetric beam is greater than or equal to the threshold, it is not used for synthesis.
The combining unit 211 may combine the signals by reducing the weight coefficient of the asymmetric beams F _{0 to} F ₇ instead of “not used for combining” based on the asymmetric beam control signal.
Further, instead of the array antenna 1001, an antenna group including one or more antennas may be used. FIG. 5 is a diagram showing the configuration of the receiving apparatus 220 in that case. The receiving apparatus 220 in FIG. 5 has a configuration in which the array antenna 1001 is replaced with the antenna group 221 and the beam forming unit 1003 is deleted as compared with the receiving apparatus 200 in FIG. FIG. 6 is a diagram showing the arrangement of the antenna group 221 and the beam pattern.

As shown in FIG. 6, the antenna group 221 arranges 12 directional antennas on the roof of the car, and generates a beam pattern similar to that in FIG. Therefore, the beam forming unit 1003 is not necessary. Other operations are the same as those of the receiving apparatus 200 of FIG.
(Embodiment 3)
FIG. 7 shows a configuration of receiving apparatus 300 according to Embodiment 3 of the present invention. The receiving apparatus 300 in FIG. 7 has a configuration in which the beam combining unit 1005 is replaced with a beam selecting unit 301, as compared with the receiving apparatus 1000 in FIG. FIG. 8 is a diagram illustrating a configuration of the beam selection unit 301. Compared with the beam combining unit 201 in FIG. 4, the beam selecting unit 301 has a configuration in which the combining unit 211 is replaced with a selecting unit 311 and the function of the power measuring unit 312 is changed.

Hereinafter, the operation of the receiving apparatus 300 will be described. In the beam selector 301, the ROM table 213 performs the same operation as that of the beam combiner 201 in FIG. The operation of the power measuring unit 312 is different from the power measuring unit 212 in the beam combining unit 201 of FIG. 4 in that a beam selection signal is generated instead of the asymmetric beam control signal. The beam selection signal is information indicating which of the frequency axis signals F _{0 to} F ₇ is selected. The power measurement unit 312 generates a beam selection signal so as to select a signal having the maximum power among the frequency axis signals related to the symmetric beam.

The selection unit 311 selects one signal from F _{0 to} F ₇ based on the beam selection signal, and outputs it to the error correction unit.
Other operations are the same as those of the receiving apparatus 1000 in FIG. Therefore, when d = 3λ / 8, there is no asymmetric beam, and as a result, the receiving apparatus 300 performs exactly the same operation as the receiving apparatus 1000 in FIG. On the other hand, when d = λ / 2, there is an asymmetric beam, and control regarding the asymmetric beam is performed as described above.

With the above configuration, it is possible to prevent the reception performance from being deteriorated without being affected by the Doppler spread by controlling so as not to select the asymmetric beam even when receiving a plurality of channels.
The power measurement unit 312 may generate a beam selection signal as follows. With this configuration, when the power of each beam of the symmetric beam is small and the power of the asymmetric beam is large, the asymmetric beam can be selected and output.

(1) Even if the power of the asymmetric beam is the maximum among all beams, the frequency axis signal for the asymmetric beam is not selected when the ratio or difference from the maximum power of the symmetric beam is equal to or less than a threshold value.
Further, instead of the array antenna 1001, an antenna group including one or more antennas may be used. FIG. 9 is a diagram showing the configuration of the receiving device 320 in that case. The receiving apparatus 320 in FIG. 9 has a configuration in which the array antenna 1001 is replaced with the antenna group 221 and the beam forming unit 1003 is deleted as compared with the receiving apparatus 300 in FIG.

The antenna group 221 is as shown in FIG. 6, and the beam forming unit 1003 is unnecessary. Other operations are the same as those of the receiving apparatus 300 in FIG.
(Embodiment 4)
FIG. 10 shows a configuration of receiving apparatus 400 according to Embodiment 4 of the present invention. The receiving apparatus 400 in FIG. 10 has a configuration in which a beam correcting unit 401 is added and the configuration of the beam combining unit 402 is replaced as compared with the receiving apparatus 1000 in FIG.

FIG. 11A is a diagram illustrating the configuration of the beam correction unit 401. The beam correction unit 401 includes a correction unit 411 and a ROM table 412. FIG. 11B is a diagram illustrating the configuration of the beam combining unit 402. The beam combining unit 402 includes a combining unit 421, a BER (Bit Error Rate) measuring unit 422, and a ROM table 423.
Hereinafter, the operation of the receiving apparatus 400 will be described. The beam correction unit 401 knows which channel the user has selected based on the channel selection information. The ROM table 412 outputs an asymmetric beam conversion signal based on the channel selection information. Asymmetric beam converted signal is a signal indicating an inner asymmetric beam frequency axis signal F ₀ to F _7, the other beam used for the operation. The ROM table 412 may store the aforementioned signal for each channel.

In the case of d = λ / 2 having the beam pattern of FIG. 19B, the correction unit 411 performs the following complex subtraction on the asymmetric beam B ₄ and outputs it, and outputs the other symmetric beams B _{0 to} B ₃ , B ₅ to B ₇ is output as it is.

B _{4_1} = B ₄ -B ₅ ... <Formula 3-1>
B _{4_2} = B ₄ -B ₃ ... <Formula 3-2>

B ₅ has a portion where the beam pattern overlaps with B _4, and B _{4_1} removes the reception signal of θ = 0 ° from B ₄ and can be regarded as a beam output having a peak only at θ = 180 °. Similarly, B ₃ has a portion where the beam pattern overlaps with B _4, and B _{4_2} removes the received signal of θ = 180 ° from B ₄ and can be regarded as a beam output having a peak only at θ = 0 °.

A plurality of FFT unit 1004 performs FFT respectively output beam modifying unit 401, a frequency-axis signal _{F 0 ~F 3, F 4_1,} F 4_2, and outputs the F ₅ to F _7.
The beam combining unit 402 knows which channel the user has selected based on the channel selection information. The ROM table 423 outputs asymmetric beam information based on the channel selection information. Asymmetric beam information in this example is information indicating that F _{4_1} and F _{4_2} is a signal that is based on an asymmetric beam traveling direction of the vehicle as an axis. The ROM table 423 may store the previous day's information for each channel.

BER measurement unit 422 F _{4_1,} perform BER measurements F _{4_2,} it outputs an asymmetrical beam selection signal. Asymmetric beam selection signal with respect to the asymmetric beam, the frequency-axis signal F _{4_1,} which is information indicating whether to use in the synthesis either F _{4_2.} Combining unit 421 on the basis of the asymmetrical beam selection signal, performs synthesis using one of the frequency-axis signal _{F 0 ~F 3, F 5 ~F} 7, and F _{4_1} and F _{4_2,} and outputs the error correction unit.

Other operations are the same as those of the receiving apparatus 1000 in FIG. Therefore, when d = 3λ / 8, there is no asymmetric beam, and as a result, the receiving apparatus 400 performs exactly the same operation as the receiving apparatus 1000 in FIG. On the other hand, when d = λ / 2, there is an asymmetric beam, and control regarding the asymmetric beam is performed as described above.
With the above configuration, even when receiving a plurality of channels, the influence of Doppler broadening in the asymmetric beam can be reduced, and deterioration of reception performance can be prevented.

  Further, instead of the beam combining unit 402, a configuration using a beam selecting unit may be used. FIG. 12 is a diagram illustrating a configuration of the receiving device 430 in that case. The receiving apparatus 430 in FIG. 12 has a configuration in which the beam combining unit 402 is replaced with a beam selecting unit 431, compared to the receiving apparatus 400 in FIG. FIG. 13 is a diagram illustrating a configuration of the beam selection unit 431. Compared with the beam combining unit 402 in FIG. 11, the beam selecting unit 431 has a configuration in which the combining unit 421 is replaced with the selecting unit 441 and a power measuring unit 442 is added.

Hereinafter, the operation of the receiving device 430 will be described. The beam selection unit 431 knows which channel the user has selected based on the channel selection information. The BER measuring unit 422 and the ROM table 423 operate in the same manner as the beam combining unit 402 in FIG. However asymmetrical beam selection signal with respect to the asymmetric beam is information indicating whether the candidate of the selection signal frequency-axis signal F _{4_1,} either F _{4_2} in the selection section 441. Performs a power measurement of the power measurement unit 442 frequency domain signal _{F 0 ~F 3, F 5 ~F} 7, one of the power measurement of the frequency-axis signal F _{4_1} and F _{4_2} based on asymmetric beam selection signal, maximum power A beam selection signal is output so as to select a signal having.

Selecting unit 441 on the basis of the beam selection _{signal, F 0 ~F 3, F 4_1} , F 4_2, by selecting one signal among the F ₅ to F _7, and outputs the error correction unit.
Other operations are the same as those of the receiving apparatus 400 of FIG. Therefore, when d = 3λ / 8, there is no asymmetric beam, and as a result, the receiving apparatus 430 performs exactly the same operation as the receiving apparatus 1000 in FIG. On the other hand, when d = λ / 2, there is an asymmetric beam, and control regarding the asymmetric beam is performed as described above.

With the above configuration, even when receiving a plurality of channels, the influence of Doppler broadening in the asymmetric beam can be reduced, and deterioration of reception performance can be prevented.
Further, instead of the array antenna 1001, an antenna group including one or more antennas may be used. FIGS. 14A and 14B are diagrams showing the configuration of receiving apparatuses 450 and 460 in that case, respectively. Compared with the receiving apparatus 400 in FIG. 10, the receiving apparatus 450 in FIG. 14A has a configuration in which the array antenna 1001 is replaced with the antenna group 221 and the beam forming unit 1003 is omitted. Compared with the receiving apparatus 430 in FIG. 12, the receiving apparatus 460 in FIG. 14B has a configuration in which the array antenna 1001 is replaced with the antenna group 221 and the beam forming unit 1003 is omitted.

The antenna group 221 is as shown in FIG. 6, and the beam forming unit 1003 is unnecessary. Other operations are the same as those of the receiving apparatus 400 of FIG. 10 and the receiving apparatus 430 of FIG.
(Embodiment 5)
FIG. 15 (a) is a diagram illustrating a configuration of receiving apparatus 500 according to Embodiment 5 of the present invention. The receiving apparatus 500 in FIG. 15A has a configuration in which the configuration of the array antenna 501 is replaced and an antenna control unit 502 is added, as compared with the receiving apparatus 1000 in FIG. FIG. 15B is a diagram illustrating the configuration of the antenna control unit 502. The antenna control unit 502 includes a ROM table 511. FIG. 15C is a diagram showing the configuration of the array antenna 501. The array antenna 501 has a configuration in which the number of antenna elements is increased to 16, compared to the array antenna 1001 in FIG.

  Hereinafter, the operation of receiving apparatus 500 will be described. The antenna control unit 502 knows which channel the user has selected based on the channel selection information. The ROM table 511 outputs an on / off control signal to each antenna element based on the channel selection information. The on / off control signal is a signal for controlling whether or not each antenna element is turned on. The ROM table 511 may store whether or not each antenna element is turned on for each channel.

The array antenna 501 turns each element on or off according to an on / off control signal.
If d = 3λ / 16, turn on element # 2N (N = 0, 1, ..., 7) and turn off element # 2N + 1 (N = 0, 1, ..., 7) The ideal beam pattern identical to that shown in FIG. 19 (a) can be generated. Also, for example, when receiving a channel twice the wavelength of the channel, if the eight consecutive elements are turned on and the other eight elements are turned off, the same ideal beam pattern as in FIG. Can be generated. Other operations are the same as those of the receiving apparatus 1000 in FIG.

With the above configuration, even when receiving multiple channels, each element of the array antenna can be turned on or off, and the antenna element spacing to be turned on can be ideal with respect to the wavelength, and reception is not affected by the Doppler spread. Degradation of performance can be prevented.
(Embodiment 6)
FIG. 16 (a) is a diagram illustrating a configuration of receiving apparatus 600 according to Embodiment 6 of the present invention. The receiving apparatus 600 in FIG. 16A has a configuration in which the configuration of the array antenna 601 is replaced and an antenna control unit 602 is added as compared with the receiving apparatus 1000 in FIG. FIG. 16B is a diagram illustrating the configuration of the antenna control unit 602. The antenna control unit 602 includes a ROM table 611 and an antenna movement signal generation unit 612. FIG. 16C is a diagram showing the configuration of the array antenna 601. The array antenna 601 has a configuration in which a rail 621 is added as compared with the array antenna 1001 of FIG.

  Hereinafter, the operation of receiving apparatus 600 will be described. The antenna control unit 602 knows which channel the user has selected based on the channel selection information. The ROM table 611 outputs element spacing information based on the channel selection information. The element spacing information is a signal indicating the element spacing d (= 3λ / 8) that is the same ideal beam pattern as in FIG. The ROM table 611 may store the aforementioned element spacing for each channel. The antenna movement signal generation unit 612 outputs an antenna movement signal for moving each element of the array antenna so as to have an interval indicated by the element interval information.

Each element of the array antenna 601 moves on the rail 621 according to the antenna movement signal so as to have the above-described element spacing. Other operations are the same as those of the receiving apparatus 1000 in FIG.
With the above configuration, the element spacing of the array antenna can be ideal with respect to the wavelength even when receiving a plurality of channels, and deterioration of reception performance can be prevented without being affected by the Doppler spread.

In the first to sixth embodiments, the number of elements is 8, and the element spacing of an ideal beam pattern
d = 3λ / 8. Similarly to FIG. 19 (a), each beam has a symmetrical shape with the traveling direction as an axis, and the beam pattern is not limited to this as long as the beam width becomes narrower as it moves away from the traveling direction and approaches the perpendicular direction.
In the first to sixth embodiments, beam synthesis or beam selection is performed using the output of the FFT unit 1004. However, the input of the FFT unit 1004 or signals of other blocks may be used, but the present invention is not limited thereto.

In the first to sixth embodiments, the beam forming unit, the beam combining unit, the beam selecting unit, and the antenna control unit perform processing using the ROM table. As long as the same function can be realized, processing may be performed using a logic circuit or the like, but is not limited thereto.
In the first to sixth embodiments, the beam forming unit is configured by a spatial DFT, but may be configured by a spatial FFT which is a kind of spatial DFT.

In Embodiments 1 to 6, the array antenna is installed on the roof. However, for example, a film antenna may be attached to glass as an array antenna, and the present invention is not limited thereto.
Although the beam forming unit is configured with a spatial DFT, it may be configured with a spatial FFT which is a kind of spatial DFT.

In the first to fourth embodiments, the operation in the case where the reception channel has the element spacing d = λ / 2 has been described as an example. Even when the element spacing has other values, it is sufficient to operate so as to have a similar function.
In the fifth embodiment, as an example, the operation in the case of switching from the reception channel satisfying d = 3λ / 16 to the case of receiving a channel twice the wavelength has been described. Even when other channels are received, it is sufficient to operate so as to have a similar function.

In Embodiments 2, 3, 5, and 6, the beam conversion unit 101 described in Embodiment 1 may be added. As a result, both the increase in circuit scale and the deterioration in reception performance can be prevented even when receiving a plurality of channels.
In the second to fourth embodiments, the beam combining unit or the beam selecting unit performs combining or selection based on the result of power measurement. However, BER, C / N (Carrier to Noise power ratio), and reliability for each carrier are used. Processing may be performed based on measurement results such as sex information (CSI: Carrier State Information), but is not limited thereto.

Also in the fourth embodiment, but we have selected one of the frequency-axis signal F _{4_1} and F _{4_2} based on the BER measurement result by the beam combining unit 402 and the beam selector 431, a power, C / N, the measurement of such CSI You may select based on a result, but it is not restricted to these.
In the second to fourth embodiments, the antenna group in FIG. 6 is configured with 12 directional antennas. For example, a beam pattern similar to that in FIG. 6 may be generated with one directional antenna. What is necessary is just to comprise with the above antenna.

In the second to fourth embodiments, the antenna group in FIG. 6 is installed on the roof. However, for example, a film antenna may be attached to glass to generate a beam pattern similar to that in FIG. Well, not limited to these.
In the first embodiment, the core D of the spatial DFT is changed by Expression 1-8. However, in this example of d = λ / 2, the value is not limited to this value as long as all directions can be covered with 7 beams or less. Other methods such as a method using a spatial FFT, which is a kind, may be used.

In the first embodiment, the direction of each beam can be arbitrarily changed by appropriately setting the change of the core W of the spatial DFT, and other methods such as a method using a spatial FFT which is a kind of spatial DFT. It may be realized with.
In the fourth embodiment, the beam correction unit 402 subtracts the adjacent beam from the asymmetric beam as shown in Equations 3-1 and 3-2. However, the calculation is not limited to this.

In the sixth embodiment, each element is moved on the rail 621 by the array antenna 601, but the present invention is not limited to this as long as the function of varying the element spacing can be realized.
Further, all of the processes in the first to sixth embodiments may be configured by hardware, or at least a part may be configured by software. In particular, if the processing unique to the present invention is configured by software, there is an advantage that the degree of freedom in design increases.

Further, the object of the present invention can be realized by describing the processing in the first to sixth embodiments as a program in the program memory and performing the demodulation processing in real time using the CPU.
The configurations of all the embodiments described above may be realized as an LSI that is typically an integrated circuit. These may be individually made into one chip, or may be made into one chip so as to include all or a part of the configuration of the above-described embodiment.

The name used here is LSI, but it may also be called IC, system LSI, super LSI, or ultra LSI depending on the degree of integration.
Further, the method of circuit integration is not limited to LSI's, and implementation using dedicated circuitry or general purpose processors is also possible. An FPGA (Field Programmable Gate Array) that can be programmed after manufacturing the LSI or a reconfigurable processor that can reconfigure the connection and setting of circuit cells inside the LSI may be used.

  Further, if integrated circuit technology comes out to replace LSI's as a result of the advancement of semiconductor technology or a derivative other technology, it is naturally also possible to carry out function block integration using this technology. Biotechnology can be applied.

  The receiving apparatus, receiving method, and program according to the present invention can be applied to a terrestrial digital broadcast receiving apparatus, a wireless receiver, and the like.

3 is a diagram illustrating a configuration of a reception device in Embodiment 1. FIG. FIG. 3 is a diagram showing a configuration of a beam forming unit and a beam pattern in the first embodiment. FIG. 11 is a diagram illustrating a configuration of a receiving device in a second embodiment. 6 is a diagram illustrating a configuration of a beam combining unit in Embodiment 2. FIG. FIG. 20 is a diagram illustrating another example of a configuration of a reception device in Embodiment 2. FIG. 11 is a diagram illustrating an arrangement of antenna groups and a beam pattern in another example of the receiving apparatus in the second embodiment. FIG. 10 is a diagram illustrating a configuration of a reception device in a third embodiment. FIG. 10 is a diagram illustrating a configuration of a beam selection unit in a third embodiment. FIG. 38 is a diagram illustrating another example of a configuration of a receiving device in Embodiment 3. FIG. 10 is a diagram illustrating a configuration of a reception device in a fourth embodiment. It is a figure which shows the structure of the beam correction part in Embodiment 4, and a beam synthetic | combination part. FIG. 38 is a diagram illustrating another example of a configuration of a reception device in Embodiment 4. FIG. 25 is a diagram illustrating a configuration of a beam selection unit in another example of a reception device in the fourth embodiment. FIG. 25 is a diagram illustrating a configuration of another example of a receiving device in a fourth embodiment. FIG. 10 is a diagram illustrating a configuration of a receiving device, an antenna control unit, and an array antenna in a fifth embodiment. FIG. 10 is a diagram illustrating a configuration of a receiving device, an antenna control unit, and an array antenna in a sixth embodiment. It is a figure which shows the structure of a receiver and an array antenna. It is a figure which shows the structure of a beam formation part. It is a figure which shows a beam pattern.

Explanation of symbols

100, 200, 220, 300, 320, 400, 430, 450, 460, 500, 600, 1000 Receiver 101, 1003 Beam forming unit 111, 213, 412, 423, 511, 611 ROM table 201, 402, 1005 Beam Combining unit 211, 421 Combining unit 212, 312, 442 Power measuring unit 221 Antenna group 301, 431 Beam selecting unit 311, 441 Selecting unit 401 Beam modifying unit 411 Modifying unit 422 BER measuring unit 501, 601, 1001 Array antenna 502, 602 Antenna control unit 612 Antenna movement signal generation unit 621 Rail 1002 Tuner 1004 FFT unit 1011 Complex adder 1012 Rotation operator

Claims (34)

An array antenna for receiving radio waves,
The element spacing of the array antenna is determined such that each beam has a symmetric shape with the moving direction as an axis at a specific reception frequency, and the beam width becomes narrower as it moves away from the moving direction in a direction perpendicular to the moving direction.
With respect to the received signals of each element of the array antenna, when the reception frequency is the specific value, spatial DFT (Discrete Fourier Transform) is performed and divided into a plurality of beams, and the reception frequency is the specific value. And a receiving apparatus configured to include a beam forming unit that changes the direction of each beam while transforming the spatial DFT calculation into a plurality of beams when the calculation is different.   The receiving apparatus according to claim 1, wherein the beam forming unit deforms the spatial DFT calculation so that the number of beams covering all directions is equal to or less than the number of beams covering all directions at the specific reception frequency.   The receiving apparatus according to claim 1, wherein the deformation of the spatial DFT calculation in the beam forming unit is a change of a nucleus W of the DFT.   4. The reception according to claim 3, wherein the beam forming unit includes a table that stores a deformation pattern of the core W of the DFT for each reception frequency, and performs the deformation of the spatial DFT operation by reading the previous deformation pattern from the table. apparatus. An antenna group composed of one or more antennas for receiving radio waves;
Using the antenna group, a beam pattern is determined such that each beam has a symmetric shape with the moving direction as an axis at a specific reception frequency, and the beam width becomes narrower as it moves away from the moving direction at a right angle,
Beam synthesis for synthesizing each beam after processing based on a predetermined standard for a beam that does not have a symmetric shape among the beams when the reception frequency is different from the specific value Receiving device configured to include a unit. The antenna group is composed of array antennas,
Further, it is configured to include a beam forming unit that performs an operation on the received signal of each element of the array antenna and outputs the signal divided into a plurality of beams,
The receiving apparatus according to claim 5, wherein an element interval of the array antenna is determined so as to be the beam pattern at a specific reception frequency.   The receiving apparatus according to claim 5, wherein the beam combining unit provides the predetermined reference according to the signal quality of each beam.   The receiving apparatus according to claim 7, wherein the beam combining unit is not used for combining a beam that does not have the symmetric shape regardless of signal quality, or reduces the weighting.   8. The beam combining unit according to claim 7, wherein when the signal quality of the beam not having the symmetric shape is equal to or lower than a threshold value, the beam combining unit is not used for combining the beam not having the symmetric shape or lowers the weight. The receiving device described.   The beam combining unit has the symmetric shape when the ratio or difference between the signal quality of the beam having no symmetric shape and the total signal quality of the beam having the symmetric shape is equal to or less than a threshold value. The receiving apparatus according to claim 7, wherein the beam that is not used is not used for synthesis or the weighting is lowered.   8. The beam combining unit is not used for combining for a beam not having the symmetric shape or lowering the weight when the total signal quality of the beam having the symmetric shape is equal to or greater than a threshold value. The receiving device described. An antenna group composed of one or more antennas for receiving radio waves;
Using the antenna group, a beam pattern is determined such that each beam has a symmetric shape with the moving direction as an axis at a specific reception frequency, and the beam width becomes narrower as it moves away from the moving direction at a right angle,
When the reception frequency is different from the specific value, processing is performed based on a predetermined criterion for each of the beams, particularly beams that do not have a symmetric shape, and then one of the beams is selected. A receiving apparatus including a beam selecting unit to select. The antenna group is composed of array antennas,
Further, it is configured to include a beam forming unit that performs an operation on the received signal of each element of the array antenna and outputs the signal divided into a plurality of beams,
The receiving apparatus according to claim 12, wherein an element interval of the array antenna is determined so as to be the beam pattern at a specific reception frequency.   The receiving apparatus according to claim 12 or 13, wherein the beam selection unit provides the predetermined reference according to the signal quality of each beam.   The receiving apparatus according to claim 14, wherein the beam selection unit does not select a beam that does not have the symmetric shape regardless of signal quality.   The beam selection unit may have a ratio or difference with a maximum signal quality of a beam having a symmetric shape that is equal to or less than a threshold even if the signal quality of the beam having no symmetric shape is the maximum among all beams. The receiving apparatus according to claim 14, wherein the beam that does not have the symmetrical shape is not selected. An antenna group composed of one or more antennas for receiving radio waves;
Using the antenna group, a beam pattern is determined such that each beam has a symmetric shape with the moving direction as an axis at a specific reception frequency, and the beam width becomes narrower as it moves away from the moving direction at a right angle,
A beam correction unit that performs an operation with another beam on a beam that does not have a symmetric shape among the plurality of beams when a reception frequency is different from the specific value;
When the reception frequency is different from the specific value, the output from the beam correction unit regarding the beam not having the symmetrical shape is processed based on a predetermined standard, and then the beams are combined. A receiving apparatus including a beam combining unit. An antenna group composed of one or more antennas for receiving radio waves;
Using the antenna group, a beam pattern is determined such that each beam has a symmetric shape with the moving direction as an axis at a specific reception frequency, and the beam width becomes narrower as it moves away from the moving direction at a right angle,
A beam correction unit that performs an operation with another beam on a beam that does not have a symmetric shape among the plurality of beams when a reception frequency is different from the specific value;
When the reception frequency is different from the specific value, the output from the beam correction unit regarding the beam not having the symmetric shape is processed based on a predetermined reference, and one of the beams is Receiving apparatus comprising a beam selecting section for selecting one. The antenna group is composed of array antennas,
Further, it is configured to include a beam forming unit that performs an operation on the received signal of each element of the array antenna and outputs the signal divided into a plurality of beams,
The receiving apparatus according to claim 17 or 18, wherein an element interval of the array antenna is determined so as to be the beam pattern at a specific reception frequency.   The receiving apparatus according to any one of claims 17 to 19, wherein the calculation in the beam correction unit is subtraction of an adjacent beam from a beam not having the symmetric shape.   The receiving apparatus according to any one of claims 17, 19, and 20, wherein the beam combining unit provides the predetermined reference according to signal quality of the calculation result regarding the beam not having the symmetric shape.   The receiving apparatus according to any one of claims 18 to 20, wherein the beam selection unit provides the predetermined reference according to a signal quality of the calculation result regarding the beam not having the symmetric shape.   The said beam correction part has a table which memorize | stored the information regarding the beam which does not have the said symmetrical shape with respect to each receiving frequency, Reads out the said information from the said table, and processes it to any one of Claims 17-22 The receiving device described. An array antenna for receiving radio waves,
An antenna control unit for outputting a control signal for turning on or off each element of the array antenna;
A calculation is performed on the received signal of each element of the array antenna, and a beam forming unit that outputs the signal divided into a plurality of beams is configured.
Each element of the array antenna is turned on or off based on the control signal output from the antenna controller,
The element spacing of the array antenna is such that each beam has a symmetric shape about the moving direction at a specific reception frequency and is perpendicular to the moving direction with respect to a predetermined pattern for turning on or off each of the elements. The beam width is determined to become narrower as it goes away in the direction,
The reception device that generates and outputs the control signal based on a predetermined reference when the reception frequency is different from the specific value.   25. The receiving apparatus according to claim 24, wherein the predetermined reference of the antenna control unit is that an interval between elements to be turned on is the same as that when the reception frequency is the specific value. An array antenna for receiving radio waves,
An antenna control unit for outputting a control signal for moving each element of the array antenna;
A beam forming unit that performs an operation on a reception signal of each element of the array antenna and outputs a plurality of beams, and
Each element of the array antenna moves so as to satisfy an element interval such that each beam has a symmetrical shape with the moving direction as an axis at each reception frequency, and the beam width becomes narrower as it moves away from the moving direction at a right angle. Receiving device.   27. The receiving device according to claim 26, wherein the array antenna is disposed on a rail, and each element is movable on the rail.   The receiving apparatus according to any one of claims 7 to 11, 14 to 16, 21, and 22, wherein the signal quality is power, C / N, error rate, or reliability information.   The beam combining unit includes a table that stores information on the beam that does not have the symmetric shape with respect to each reception frequency, and reads and processes the information from the table. 24. The receiving device according to any one of items 23 to 23.   The said beam selection part has a table which memorize | stored the information regarding the beam which does not have the said symmetrical shape with respect to each receiving frequency, The said information is read from the said table, and it processes it. The receiving apparatus of any one of -24.   The receiving apparatus according to any one of claims 24 to 27, wherein the antenna control unit includes a table that stores the control signal for each reception frequency, and reads and processes the signal from the table.   The receiving apparatus according to any one of claims 6 to 11, 13 to 16, and 19 to 31, wherein the operation of the beam forming unit is a spatial DFT (Discrete Fourier Transform). An array antenna for receiving radio waves,
The element spacing of the array antenna is determined such that each beam has a symmetric shape with the moving direction as an axis at a specific reception frequency, and the beam width becomes narrower as it moves away from the moving direction in a direction perpendicular to the moving direction.
With respect to the received signals of each element of the array antenna, when the reception frequency is the specific value, spatial DFT (Discrete Fourier Transform) is performed and divided into a plurality of beams, and the reception frequency is the specific value. A receiving method configured to include a beam forming step in which the spatial DFT calculation is modified and divided into a plurality of beams and the direction of each beam is changed.   The program which described the signal processing procedure for performing the receiving method of Claim 33.

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