Antenna device, estimation method, and program

Abstract

To provide an antenna device, an estimation method, and a program that facilitate adaptive beamforming in analog beamforming.SOLUTION: An antenna device 1 according to one embodiment of the present disclosure includes an array antenna 11 having a plurality of antenna elements, a branching section 12 that branches a received signal of each of the plurality of antenna elements into a first branch signal and a second branch signal, a first combining section 17 that combines the first branch signal that has passed through a first attenuation section 13 and a first phase shift section 14, a second combining section 18 that combines the second branch signal that has passed through a second attenuation section 15 and a second phase shift section 16, and an optimization section 19 that sets a second attenuation amount corresponding to one or more antenna elements including one antenna element to zero and sets a second attenuation amount corresponding to antenna elements other than the one or more antenna elements to a maximum, and estimates a received signal of one antenna element from the second combined signal.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present disclosure relates to an antenna device, an estimation method, and a program. [Background technology]

[0002] A technology called phased array antenna is known. This technology combines multiple antenna elements and weights the amplitude and phase of the signal from each element to optimize it, thereby controlling the direction of signal propagation (called a beam). Phased array antennas have a control method called adaptive beamforming. This control method optimizes the shape of the beam in the receiving system to suit the environment surrounding the antenna. This control method is mostly realized in digital beamforming, and there was an issue that it would be difficult to realize in analog beamforming.

[0003] Patent Document 1 describes that "a phased array antenna providing a radiation pattern having at least one communication beam is provided, the phased array antenna comprising: a plurality of antenna elements, each antenna element having an antenna element signal having a phase relationship and an amplitude relationship with other element signals; a digital signal processing arrangement providing a digital beamforming network; and an analog beamforming network reducing exposure of the digital signal processing arrangement to an interference signal, the analog beamforming network providing analog beamforming weights to signals received from the plurality of antenna elements to generate a null in the radiation pattern in a direction corresponding to the interference signal, and the digital beamforming network providing digital beamforming weights for each of the at least one communication beam to signals received from the analog beamforming network, such that at least one communication beam is provided by a composite radiation pattern of the antenna." Patent Document 1 does not disclose a technology for performing adaptive analog beamforming control.

[0004] Patent Document 2 states that "variable phase shifters 3-1 to 3-N shift the phase of each of N radio signals received by an array antenna consisting of N antenna elements by a predetermined phase shift amount, and a combiner combines the phase-shifted N radio signals to output a combined radio signal. A demodulator demodulates the combined radio signal to a baseband signal, and a beam control circuit perturbs each phase shift amount by a predetermined shift amount using an M-LMS method based only on the demodulated baseband signal to calculate the amount of change in the baseband signal from the variable amplifier before and after perturbation, and calculates each phase shift amount and gain for directing the main beam in a predetermined direction so that the root mean square of the error signal is minimized based on an error signal between the baseband signal and its code discrimination value, thereby performing adaptive beam control." Patent Document 2 does not disclose a technology for performing adaptive analog beamforming control. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Special Publication No. 2013-529870 [Patent Document 2] JP 2002-076748 A Summary of the Invention [Problem to be solved by the invention]

[0006] When adaptive beamforming is performed, the antenna device needs to measure the received signal of each antenna element. When adaptive beamforming is performed in analog beamforming, the high-frequency circuit provided around each antenna element needs to separate and process a part of the received signal. In this case, the circuit size and power consumption increase, making it difficult to realize adaptive beamforming in analog beamforming. Adaptive beamforming has often been realized in digital beamforming.

[0007] The present disclosure has been made in consideration of such problems, and has an object to provide an antenna device, an estimation method, and a program that facilitate adaptive beamforming in analog beamforming. [Means for solving the problem]

[0008] An antenna device according to an aspect of the present disclosure includes: an array antenna having a plurality of antenna elements; a branching unit that branches a received signal from each of the plurality of antenna elements into a first branch signal and a second branch signal; a first attenuation unit capable of changing a first attenuation amount of each of the first branch signals; a first phase shift unit capable of changing a first phase shift amount of each of the first branch signals; a second attenuation unit capable of changing a second attenuation amount of each of the second branch signals; a second phase shift unit capable of changing a second phase shift amount of each of the second branch signals; a first combining unit that combines the first branched signals that have passed through the first attenuation unit and the first phase shift unit to generate a first combined signal; a second combining unit that combines the second branched signals that have passed through the second attenuation unit and the second phase shift unit to generate a second combined signal; an optimization unit that, when optimizing a first weighting amount including the first attenuation amount and the first phase shift amount, sets a second attenuation amount corresponding to one or more antenna elements including one antenna element to zero, sets a second attenuation amount corresponding to antenna elements other than the one or more antenna elements to a maximum, and estimates a received signal of the one antenna element from the second composite signal; Equipped with.

[0009] The estimation method according to one embodiment of the present disclosure includes: an array antenna having a plurality of antenna elements; a branching unit that branches a received signal from each of the plurality of antenna elements into a first branch signal and a second branch signal; a first attenuation unit capable of changing a first attenuation amount of each of the first branch signals; a first phase shift unit capable of changing a first phase shift amount of each of the first branch signals; a second attenuation unit capable of changing a second attenuation amount of each of the second branch signals; a second phase shift unit capable of changing a second phase shift amount of each of the second branch signals; a first combining unit that combines the first branched signals that have passed through the first attenuation unit and the first phase shift unit to generate a first combined signal; a second combining unit that combines the second branched signals that have passed through the second attenuation unit and the second phase shift unit to generate a second combined signal; An estimation method for an antenna device comprising: When optimizing the first weighting amount including the first attenuation amount and the first phase shift amount, a second attenuation amount corresponding to one or more antenna elements including one antenna element is set to zero, and a second attenuation amount corresponding to antenna elements other than the one or more antenna elements is set to a maximum, and a received signal of the one antenna element is estimated from the second composite signal.

[0010] A program according to an embodiment of the present disclosure includes: an array antenna having a plurality of antenna elements; a splitter that splits a received signal from each of the plurality of antenna elements into a first branch signal and a second branch signal; a first attenuation unit capable of changing a first attenuation amount of a first branched signal; a first phase shift unit capable of changing a first phase shift amount of a first branched signal; a second attenuation unit capable of changing a second attenuation amount of the second branch signal; a second phase shift unit capable of changing a second phase shift amount of the second branched signal; a first combining unit that combines the first branched signals that have passed through the first attenuation unit and the first phase shift unit to generate a first combined signal; a second combining unit that combines the second branched signals that have passed through the second attenuation unit and the second phase shift unit to generate a second combined signal; A computer provided in the antenna device, When optimizing the first weighting amount including the first attenuation amount and the first phase shift amount, a second attenuation amount corresponding to one or more antenna elements including one antenna element is set to zero, and a second attenuation amount corresponding to antenna elements other than the one or more antenna elements is set to a maximum, and a process is executed to estimate the received signal of the one antenna element from the second composite signal. Effect of the Invention

[0011] According to the present disclosure, it is possible to provide an antenna device, an estimation method, and a program that facilitate adaptive beamforming in analog beamforming. [Brief description of the drawings]

[0012] [Figure 1] 1A and 1B are diagrams illustrating the configuration of a related antenna device. [Diagram 2] 1A and 1B are diagrams illustrating the configuration of a related antenna device. [Diagram 3] 1 is a diagram illustrating a configuration of an antenna device according to a first embodiment. [Figure 4] 10 is a diagram illustrating a configuration of an antenna device according to a second embodiment. FIG. [Diagram 5] 10A to 10C are diagrams illustrating the operation of the antenna device according to the second embodiment. [Figure 6] 10A to 10C are diagrams illustrating the operation of the antenna device according to the second embodiment. [Figure 7] 10A to 10C are diagrams illustrating the operation of the antenna device according to the second embodiment. [Figure 8] 11 is a diagram illustrating a configuration of an antenna device according to a third embodiment. FIG. [Figure 9] 13A to 13C are diagrams illustrating the operation of the antenna device according to the third embodiment. [Figure 10] 13 is a diagram illustrating the configuration of an antenna device according to a fourth embodiment. FIG. [Figure 11] 13A to 13C are diagrams illustrating the operation of the antenna device according to the fourth embodiment. [Figure 12]13 is a diagram illustrating an example of the configuration of an antenna device according to a fourth embodiment. FIG. [Figure 13] 13 is a diagram illustrating the configuration of an antenna device according to a fifth embodiment. FIG. [Figure 14] 13 is a diagram illustrating the configuration of an antenna device according to a sixth embodiment. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] <Reference example> First, a related antenna device will be described with reference to Fig. 1 and Fig. 2. Fig. 1 is a diagram illustrating the configuration of an antenna device 20 that performs adaptive beamforming. The antenna device 20 includes a plurality of antenna elements ANT1 to ANT N The system includes a plurality of weighting units 21, a synthesis unit 22, and an adaptive processor 23. N each of the plurality of antenna elements ANT1 to ANT N , the received signals at the plurality of antenna elements ANT1 to ANT N When not distinguishing between them, they may be simply called antenna elements ANT. N When they are not distinguished from each other, they may simply be referred to as the received signal x.

[0014] ω1~ω N Each of the weighting units 21 indicates a weighting amount applied by the weighting units 21. The combiner 22 combines the received signals x1 to x N The adaptive processor 23 combines the received signals x1 to x to generate a combined signal y. N and weights ω1 to ω based on the composite signal y N Optimize.

[0015] In addition, in a normal antenna device that does not perform adaptive beamforming, for example, weighting called uniform excitation is performed. Equation (1) is an equation that explains weighting by uniform excitation.

[0016]

number

[0017] FIG. 2 is a diagram for explaining the configuration of an antenna device 20a that performs adaptive forming in analog beamforming. FIG. 2 shows a configuration in the case where the MMSE (Minimum Mean Square Error) method is used. The adaptive processor 23 includes a first processing unit 231, a second processing unit 232, a multiplier unit 233, and an integrator 234. The first processing unit 231 subtracts a composite signal y from a reference signal d to generate an error signal e. The second processing unit 232 generates a conjugate signal e of the error signal e. * Generate.

[0018] The antenna device 20a separates a part of the received signal around the antenna element ANT. The multiplier 233 multiplies the separated received signal x by a conjugate signal e * The result is multiplied by and input to integrator 234. The output of integrator 234 is input to weighting unit 21.

[0019] In addition, if the vector in which the weights are arranged is vector ω, the vector in which the received signals of the antenna elements ANT are arranged is vector x, and the composite signal is y, the weights are optimized by repeated calculations (also called iterations). For example, in the MMSE steepest descent method, the weights are updated using equation (2). μ and r represent parameters used in this method. The vector ω[m], which represents the weights in the mth iteration, vector x[m], and y[m], are used to calculate the vector ω[m+1] in the next iteration.

number

[0020] EMBODIMENT 1 First, the problems that the present inventors found in the antenna device 20a of the above reference example will be described. The antenna device 20a needs to perform the above-mentioned complicated processing. In addition, a high-frequency circuit that handles the separated received signal x is required. Furthermore, there is a disadvantage that the circuit configuration needs to be changed according to the optimization method. Therefore, there is a problem that it is difficult to perform adaptive beamforming in analog beamforming. Therefore, the present disclosure realizes an antenna device that makes it easy to perform adaptive beamforming in analog beamforming.

[0021] Hereinafter, a description will be given of the antenna device according to the embodiment 1. The same components are given the same reference numerals, and the description will be omitted as appropriate.

[0022] 3 is a diagram illustrating the configuration of the antenna device 1 according to the embodiment 1. The antenna device 1 includes an array antenna 11, a plurality of branching sections 12, a plurality of first attenuation sections 13, a plurality of first phase-shifting sections 14, a plurality of second attenuation sections 15, a plurality of second phase-shifting sections 16, a first combining section 17, a second combining section 18, and an optimization section 19.

[0023] The array antenna 11 has a plurality of antenna elements ANT. The number of antenna elements may be two or more.

[0024] The branching unit 12 branches the received signal at the antenna element ANT into a first branch signal and a second branch signal. The first attenuation unit 13 and the first phase shift unit 14 may be disposed between each branching unit 12 and the first combiner unit 17. The second attenuation unit 15 and the second phase shift unit 16 may be disposed between each branching unit 12 and the second combiner unit 18. The branching unit 12 may branch the received signal at the antenna element ANT into three or more branch signals.

[0025] The first attenuation unit 13 is configured to be able to change the attenuation amount (referred to as the first attenuation amount) of each first branch signal. The first attenuation unit 13 may be an attenuator. It is preferable that the maximum attenuation amount is large enough to stop the propagation of the first branch signal. The first attenuation unit 13 may be a switch (referred to as the first switch) disposed in the transmission path of the first branch signal. For example, the attenuation amount of the first branch signal may be treated as zero when the first switch is closed, and the attenuation amount of the first branch signal may be treated as maximum when the first switch is opened. It is not necessary that the first switch is provided for each first branch signal. A changeover switch for switching the first branch signal input to the first combiner 17 may function as the first attenuation unit 13. The first attenuation unit 13 may also be a variable gain amplifier.

[0026] The first phase shift unit 14 is configured to be able to change the phase shift amount of the first branched signal (referred to as a first phase shift amount). The first phase shift unit 14 may be a phase shifter connected in series to the first attenuation unit 13 which is an attenuator.

[0027] The second attenuation unit 15 is configured to be able to change the amount of attenuation of the second branch signal (referred to as the second attenuation amount). The second attenuation unit 15 may be an attenuator. It is preferable that the maximum amount of attenuation is large enough to stop the propagation of the second branch signal. The second attenuation unit 15 may be a switch (referred to as the second switch) arranged in the transmission path of the second branch signal. The operation of the second switch is similar to the operation of the first switch described above. The second attenuation unit 15 may also be a variable gain amplifier.

[0028] The second phase shift unit 16 is configured to be able to change the phase shift amount of the second branched signal (referred to as a second phase shift amount). The second phase shift unit 16 may be a phase shifter connected in series to the second attenuation unit 15 which is an attenuator.

[0029] The first combiner 17 generates a first combined signal by combining the first branched signals that have passed through the first attenuation unit 13 and the first phase shift unit 14. The first combiner 17 outputs the first combined signal to the optimization unit 19. A part of the first combined signal may be used for normal signal processing.

[0030] The second combiner 18 generates a second combined signal by combining the second branched signals that have passed through the second attenuation unit 15 and the second phase shift unit 16. The second combiner 18 outputs the second combined signal to the optimization unit 19. A part of the second combined signal may be used for normal signal processing.

[0031] The optimization unit 19 optimizes the first weighting amount including the first attenuation amount and the first phase shift amount. The optimization unit 19 may further optimize the second weighting amount including the second attenuation amount and the second phase shift amount. In this case, the antenna device 1 can process two beams. Note that the second attenuation unit 15, the second phase shift unit 16, and the second combiner unit 18 may be provided to optimize the first weighting amount. In this case, the optimization unit 19 does not need to optimize the second weighting amount.

[0032] When optimizing the first weighting amount, the optimization unit 19 sets the second attenuation amount corresponding to one or more antenna elements ANT including one antenna element ANT to zero. Then, the optimization unit 19 sets the second attenuation amount corresponding to antenna elements ANT other than the one or more antenna elements ANT to maximum. Then, the optimization unit 19 estimates the received signal of the one antenna element ANT from the first combined signal.

[0033] The one or more antenna elements ANT may be composed of one antenna element ANT. The one or more antenna elements ANT may be composed of a plurality of antenna elements ANT treated as a group.

[0034] The optimization unit 19 can estimate the received signal of each antenna element ANT from the second composite signal. Then, the optimization unit 19 can optimize the first weighting amount based on the estimated received signal and the first composite signal. The optimization unit 19 may further optimize the second weighting amount in a similar manner.

[0035] The optimization unit 19 may optimize the first weighting amount using an existing algorithm such as the Minimum Mean Square Error (MMSE) method, the Maximum Signal-to-Noise ratio (MSN) method, or the Directionally Constrained Minimization of Power (DCMP) method. The optimization unit 19 repeats the process of updating the first weighting amount based on the current first weighting amount, the received signals of the antenna elements ANT, and the first composite signal. In this way, the optimization unit 19 optimizes the first weighting amount.

[0036] The functions of the first synthesis unit 17, the second synthesis unit 18, and the optimization unit 19 may be realized by dedicated hardware. In addition, a part or all of each function may be realized by a general-purpose or dedicated circuit, processor, or a combination of these. These may be configured by a single chip, or may be configured by multiple chips connected via a bus. A part or all of each function may be realized by a combination of the above-mentioned circuits, etc., and a program. In addition, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), an FPGA (Field Programmable Gate Array), etc. may be used as the processor.

[0037] The antenna device 1 may include, for example, a processor, a memory, and a storage device as components not shown. The storage device stores a computer program in which the processing of the estimation method according to the first embodiment is implemented. The processor then reads the computer program from the storage device into the memory and executes the computer program. In this way, the processor may realize the function of an optimization unit 19. The processor may be a processor called an adaptive processor.

[0038] The antenna device according to the first embodiment can facilitate adaptive beamforming in analog beamforming.

[0039] The circuits through which the multiple branch signals pass can have the same configuration. In this case, the antenna device according to the first embodiment can suppress the influence of differences in paths and improve the accuracy of adaptive beamforming. This reduces the design cost of the antenna device and simplifies the configuration of the antenna device. In addition, the antenna device according to the first embodiment reduces the number of signals used in adaptive beamforming in analog beamforming. This results in a small size and low power consumption.

[0040] EMBODIMENT 2 The second embodiment is a specific example of the first embodiment. Fig. 4 is a diagram illustrating the configuration of an antenna device 100 according to the second embodiment.

[0041] The antenna device 100 is a specific example of the antenna device 1. The antenna device 100 includes an array antenna 11, a splitter 120, a first attenuator 130, a first phase shifter 140, a second attenuator 150, a second phase shifter 160, a first combining circuit 170, a second combining circuit 180, an optimization unit 190, and a control unit 200.

[0042] The splitter 120 is a specific example of the splitting unit 12. The splitter 120 preferably performs in-phase splitting and may be, for example, a Wilkinson divider. Of course, the splitter 120 may be a hybrid coupler or a coupler that imparts a phase difference to the split signal.

[0043] The first attenuator 130 is a specific example of the first attenuation section 13. The first phase shifter 140 is a specific example of the first phase shift section 14. The first attenuator 130 and the first phase shifter 140 are connected in series with each other.

[0044] The first combining circuit 170 and the second combining circuit 180 are specific examples of the first combining section 17 and the second combining section 18, respectively. The first combining circuit 170 generates a combined signal y1 by combining the first branch signals that have passed through the first attenuator 130 and the first phase shifter 140. The second combining circuit 180 generates a combined signal y2 by combining the second branch signals that have passed through the second attenuator 150 and the second phase shifter 160.

[0045] The optimization unit 190 is a specific example of the optimization unit 19. The optimization unit 19 optimizes the first weighting amount and the second weighting amount. The one or more antenna elements ANT in the first embodiment are configured by one antenna element ANT.

[0046] When optimizing the first weighting amount, the optimization unit 190 sets the second attenuation amount corresponding to one antenna element ANT to zero. Then, the optimization unit 190 sets the second attenuation amount corresponding to antenna elements ANT other than the one antenna element ANT to the maximum. Then, the optimization unit 19 estimates the reception signal x of the one antenna element ANT as the second composite signal y2. This allows the optimization unit 190 to estimate the reception signal of each antenna element ANT. Then, the optimization unit 190 repeats the process of updating the first weighting amount based on the reception signal of each antenna element ANT, the first composite signal y1, and the current first weighting amount.

[0047] When optimizing the second weighting amount, the optimization unit 190 sets the first attenuation amount corresponding to one antenna element ANT to zero. Then, the optimization unit 190 sets the first attenuation amount corresponding to antenna elements ANT other than the one antenna element ANT to the maximum. Then, the optimization unit 190 estimates the reception signal of the one antenna element ANT as the first composite signal y1. This allows the optimization unit 190 to estimate the reception signal of each antenna element ANT. Then, the optimization unit 19 repeats the process of updating the second weighting amount based on the reception signal of each antenna element ANT, the second composite signal y2, and the current second weighting amount.

[0048] The control unit 200 controls the first weighting amount and the second weighting amount. The control unit 200 sets the optimal weighting amount calculated by the optimization unit 190, and optimizes the first composite signal y1 and the second composite signal y2. The control unit 200 also sets the first attenuation amount and the second attenuation amount to zero or maximum in response to an instruction from the optimization unit 190.

[0049] Next, a specific description will be given of the operation of the antenna device 100. x1(t) to x4(t) represent the received signals of the antenna elements ANT1 to ANT4, respectively. ω1 (1) (t)~ω4 (1) (t) represents the first weighting amounts corresponding to the antenna elements ANT1 to ANT4, respectively. ATT1 to ATT4 represent the second attenuation amounts corresponding to the antenna elements ANT1 to ANT4.

[0050] The antenna device 100 optimizes the first weighting amount by repeating steps 1 to 5. (1) (t)~ω4 (1) Assume that ω1[m=0] to ω4[m=0] are set for the first weighting amount, where m represents the number of times the first weighting amount is updated.

[0051] In step 1, the antenna device 100 sets ATT1 to 0 dB and ATT2, ATT3, and ATT4 to maximum attenuation (e.g., 30 dB). In this case, x2, x3, and x4 have almost no effect on y2. The antenna device 100 stores y2 as x1.

[0052] In step 2, the antenna device 100 sets ATT2 to 0 dB and ATT1, ATT3, and ATT4 to maximum attenuation (e.g., 30 dB). In this case, x1, x3, and x4 have almost no effect on y2. The antenna device 100 stores y2 as x2.

[0053] In step 3, the antenna device 100 sets ATT3 to 0 dB and ATT1, ATT2, and ATT4 to maximum attenuation (e.g., 30 dB). In this case, x1, x2, and x4 have almost no effect on y2. The antenna device 100 stores y2 as x3.

[0054] In step 4, the antenna device 100 sets ATT4 to 0 dB and ATT1, ATT2, and ATT3 to maximum attenuation (e.g., 30 dB). In this case, x1, x2, and x3 have almost no effect on y2. The antenna device 100 stores y2 as x4.

[0055] By performing steps 1 to 4, the antenna device 100 can obtain x1 to x4. In addition, the antenna device 100 can know ω1[m=0] to ω4[m=0], and can also know y1(t). Note that y1(t) is expressed by equation (3). x i The value of x strictly varies from step to step. However, if you execute each step fast enough, i We can assume that the value of x is constant. i The average value of may be calculated.

number

[0056] FIG. 6 is a diagram for explaining the values ​​of y1 and y2 at each time. The horizontal axis represents the time axis. First, the antenna device 100 estimates x1 to x4 from y2. Then, the antenna device 100 updates the vector ω[m=0] representing the weighting amount to the vector ω[m=1]. The vector ω represents a vector having the weighting amounts ω1 to ω4 as its components. y1 is updated to the inner product of the vector ω[m=1] and the vector x. The vector x is a vector having the components x1 to x4.

[0057] Then, the antenna device 100 re-estimates x1 to x4 from y2. Then, the antenna device 100 updates the vector ω[m=1] to the vector ω[m=2]. Then, y1 is updated based on the vector ω[m=2].

[0058] After the first weighting is optimized, the antenna device 100 optimizes the second weighting in a similar manner. The antenna device 100 can handle two beams with different directions, y1 and y2, respectively.

[0059] 7 is a diagram illustrating the operation of the antenna device 100. After optimizing y1, the antenna device 100 optimizes y2 and performs communication using y1 and y2. Then, the antenna device 100 ends the communication and optimizes y1 and y2 again.

[0060] The second embodiment can achieve the same effects as the first embodiment. Moreover, the antenna device according to the second embodiment can handle two beams arriving in different directions.

[0061] EMBODIMENT 3 The third embodiment is a specific example of the first embodiment. In the third embodiment, a plurality of antenna elements ANT are treated as a group. Fig. 8 is a diagram for explaining the configuration of an antenna device 100b according to the third embodiment. An optimization unit and the like are omitted from the illustration.

[0062] In a specific example, the array antenna 11 includes four antenna elements ANT, and two antenna elements ANT are grouped together. For example, antenna elements ANT1 and ANT2 are grouped together, and antenna elements ANT3 and ANT4 are grouped together. The weighting amounts of the grouped antenna elements ANT are related to each other.

[0063] It is assumed that the antenna device 100b holds information indicating the approximate direction of arrival of the received signal. If the direction of arrival is unknown, it may be assumed that the front direction (boresight) of the array antenna 11 faces the direction of arrival.

[0064] When N antenna elements ANT are grouped together, the antenna device 100b has a total of ω NK (1) =ω NK+1 (1) e iβ =ω NK+2 (1) e 2iβ ==ω N(K+1)-1 (1) e (N-1)iβ where K is an integer equal to or greater than 1. β is the weighting factor β=kdsin(θ) when performing uniform excitation. When two antenna elements ANT are combined, ω 2K (1) =ω 2K+1 (1) e iβ It is.

[0065] In the third embodiment, the optimization unit 190 changes both the second attenuation amount and the second phase shift amount. The second weighting amount is ω i (2) where i is an integer equal to or greater than 1.

[0066] The antenna device optimizes the first weighting amount by repeating steps 1 to 3 below. i (1) ω i It is assumed that a certain weight is assigned at [m=0].

[0067] In step 1, the optimization unit 190 (2) =1,ω2 (2) =e iβ That is, the antenna device 100b sets the second attenuation amount corresponding to the antenna elements ANT1 and ANT2 to zero, and sets the second phase shift amount corresponding to the antenna element ANT2 to β. Then, the antenna device 100b sets ω3 (2) and ω4 (2) The second attenuation of the antenna device 100b is set to the maximum (e.g., 30 dB). The antenna device 100b stores the second composite signal y2 as x1'. The second composite signal y2 corresponds to a received signal when the beam direction of a two-element array antenna is oriented in the θ direction using the uniform excitation method.

[0068] In step 2, the antenna device 100b has a wavelength of ω3 (2) =1, ω4 (2) =e iβ That is, the antenna device 100b sets the second attenuation amount corresponding to the antenna elements ANT3 and ANT4 to zero, and sets the second phase shift amount corresponding to the antenna element ANT4 to β. Then, the antenna device 100b sets ω1 (2) and ω2 (2) The antenna device 100b then sets the second amount of attenuation corresponding to y2 to the maximum (for example, 30 dB).Then, the antenna device 100b stores the second combined signal y2 as x2'.

[0069] Next, we will explain step 3. In steps 1 and 2, x1', x2', ω1 (1) , ω2(1) , ω3 (1) , ω4 (1) , and y1 are obtained. ω1 (1) '[m=0]=ω1 (1) =ω2 (1) e iβ Let ω2 (1) '[m=0]=ω3 (1) =ω4 (1)iβ In this case, the information obtained in steps 1 and 2 is x1', x2', ω1 (1) '[m=0], ω2 (1) '[m=0], y1. The optimization unit 190 uses an adaptive forming algorithm for a two-element antenna to optimize ω1 (1) '[m=1] and ω2 (1) 'Calculate [m=1].

[0070] The first weight in the next iteration is ω1 (1) =ω1 (1) '[m=1], ω2 (1) =ω1 (1) '[m=1]e -iβ , ω3 (1) =ω2 (1) '[m=1], ω4 (1) =ω2 (1) '[m=1]e -iβ It is.

[0071] The weighting amounts for the grouped antenna elements ANT are not limited to those in the case of uniform excitation, and may be those in the case of using a binomial array or a Dolph-Tchebyshev array.

[0072] 9 is a diagram for explaining the operation of the antenna device 100b. After storing x1' and x2', the antenna device 100b updates the vector ω[m=0] to the vector ω[m=1]. y1 is updated based on the vector ω[m=1].

[0073] Next, the antenna device 100b stores the new x1' and x2', and updates the vector ω[m=1] to the vector ω[m=2]. y1 is updated based on the vector ω[m=2].

[0074] In the third embodiment, the number of procedures required for optimization can be reduced, thereby reducing the required calculation time. Even when the speed of change of the external situation is fast, the time until the calculation converges is short.

[0075] EMBODIMENT 4 The fourth embodiment is a specific example of the first embodiment. Fig. 10 is a diagram for explaining the configuration of an antenna device 100c according to the fourth embodiment. A splitter 120 of the antenna device 100c splits a received signal from one antenna element ANT into three or more branch signals. Any one of the branch signals is used for optimizing the other branch signals.

[0076] Branch signal S1~S n If there are branch signals S1 to S n-1 is used for normal communication. And the branch signal S n However, the branch signals S1 to S n-1 It is used to optimize the branch signal S n corresponds to the second branch signal. n-1 Each of these corresponds to a first branch signal.

[0077] The splitter 120 of the antenna device 100c splits, for example, the received signal x of each antenna element ANT into three split signals S1 to S3. The combining circuit 171 generates a combined signal y1 by combining the split signals S1 that have passed through the attenuator 131 and the phase shifter 141. The combining circuit 172 generates a combined signal y2 by combining the split signals S2 that have passed through the attenuator 132 and the phase shifter 142. The combining circuit 181 generates a combined signal y3 by combining the split signals S3 that have passed through the attenuator 151 and the phase shifter 161.

[0078] Each of the branch signals S1 to S2 corresponds to a first branch signal. The branch signal S3 corresponds to the second branch signal. The attenuators 131 and 132 correspond to the first attenuation section 13. The phase shifters 141 and 142 correspond to the first phase shift section 14. The attenuator 151 corresponds to the second attenuation section 15. The phase shifter 161 corresponds to the second phase shift section 16. The combining circuits 171 and 172 correspond to the first combining section 17. The combining circuit 181 corresponds to the second combining section 18.

[0079] 11 is a diagram illustrating the operation of the antenna device according to the fourth embodiment. n The composite signal y n is first used to optimize the composite signal y1. After the optimization of the composite signal y1 is completed, n is used to optimize the composite signal y2. After the optimization of the composite signal y2 is completed, n is used to optimize the composite signal y3. n-1 Once the optimization is complete, each composite signal is used for normal communication. Each composite signal is not used in optimizing other composite signals.

[0080] Fig. 12 is a diagram illustrating a modified configuration of the antenna device 100c according to the fourth embodiment. The antenna device 100c shown in Fig. 10 does not include the attenuator 151, and includes switches SW1 to SW3. The switches SW1 to SW3 are arranged in the periphery of the combining circuit 181. The switches SW1 to SW3 function as a second attenuation unit 15.

[0081] The antenna device 100c switches the states of the switches SW1 to SW3 so that the output end of the combiner circuit 181 is connected to an appropriate antenna element ANT. When the switches SW1 to SW3 are used, the isolation between the branched signals is greater than when the attenuator 151 is used. Therefore, when estimating the received signal of each antenna element ANT, the influence of the received signals of other antenna elements ANT is reduced.

[0082] The fourth embodiment can prevent the time for performing normal communication for branch signals other than one branch signal from becoming shorter.

[0083] EMBODIMENT 5 The fifth embodiment is a specific example of the first embodiment. A normal combiner circuit simply combines signals. In the fifth embodiment, an attenuator is provided inside the combiner circuit.

[0084] 13 is a diagram illustrating a configuration of a second combining circuit 180 according to the fifth embodiment. The second combining circuit 180 includes a plurality of attenuators 182. The attenuators 182 are provided downstream of each node where the second branch signals are joined.

[0085] The antenna device according to the fifth embodiment sets the attenuation of the attenuator 182 through which the second branch signals from one or more antenna elements ANT including one antenna element ANT pass to zero, and sets the attenuation of the attenuator 182 through which the second branch signals from the other antenna elements ANT pass to maximum.

[0086] In the fifth embodiment, the influence of branched signals from other antenna elements ANT is reduced, thereby improving the estimation accuracy of the received signal of each antenna element.

[0087] EMBODIMENT 6 The sixth embodiment is a specific example of the first embodiment. For example, the antenna device according to the first embodiment may be configured to perform full analog beamforming. However, the antenna device according to the first embodiment may be configured to perform hybrid beamforming or digital beamforming. In the hybrid forming, part of the processing performed in the antenna device is digitally processed.

[0088] 14 is a diagram illustrating an example of the configuration of an antenna device 100d according to the sixth embodiment. The antenna device 100d includes a first circuit C1 that performs analog processing and a second circuit C2 that performs digital processing. The second circuit C2 includes an ADC (Analog to Digital Converter) 210 that converts an analog signal into a digital signal. A first combining circuit 170 and a second combining circuit 180 combine the digitized branch signals.

[0089] The sixth embodiment can also achieve the same effects as the first embodiment.

[0090] In the above embodiment, the present disclosure has been described as a hardware configuration, but the present disclosure is not limited to this. The present disclosure can also be realized by having a CPU (Central Processing Unit) execute a computer program to process each component.

[0091] In the above embodiment, the program can be stored and supplied to the computer using various types of non-transitory computer readable media. The non-transitory computer readable media includes various types of tangible storage media. Examples of the non-transitory computer readable media include magnetic recording media (specifically, flexible disks, magnetic tapes, and hard disk drives), magneto-optical recording media (specifically, magneto-optical disks), CD-ROMs (Read Only Memory), CD-Rs, CD-R / Ws, semiconductor memories (specifically, mask ROMs, PROMs (Programmable ROMs), and EPROMs (Erasable PROMs)), flash ROMs, and RAMs (Random Access Memory). The program may also be supplied to the computer by various types of transitory computer readable media. Examples of the transitory computer readable media include electrical signals, optical signals, and electromagnetic waves. The transitory computer readable media can supply the program to the computer via wired communication paths such as electric wires and optical fibers, or wireless communication paths.

[0092] Additionally, although operations are depicted in a particular order, this should not be understood as requiring such operations to be performed in the particular order or sequential order depicted, or that all of the depicted operations be performed, to achieve desirable results. In certain situations, multitasking and parallel processing may be advantageous. Similarly, although details of several specific embodiments are included in the above discussion, these should not be construed as limitations on the scope of the disclosure, but rather as descriptions of features specific to particular embodiments. Certain features that are described in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment may also be implemented in multiple embodiments separately or in any suitable combination.

[0093] Although the present disclosure has been described above with reference to the embodiments, the present disclosure is not limited to the above. Various modifications that can be understood by a person skilled in the art can be made to the configuration and details of the present disclosure within the scope of the disclosure.

[0094] The present disclosure is not limited to the above-described embodiment, and can be modified as appropriate without departing from the spirit and scope of the present disclosure. [Explanation of symbols]

[0095] 20, 20a, 1, 100, 100a, 100b, 100c, 100d...Antenna device 11...Array antenna 21…Weighting section 22...Synthetic section 23…Adaptive processor 231...First processing section 232...Second processing section 233…Multiplication section 234...Integrator 12...Branch 13…First attenuation section 14...First phase shift section 15…Second attenuation section 16...Second phase shift section 17…First composite section 18...Second composite part 19, 190…Optimization section 120…Switch 130...First attenuator 140...First phase shifter 150…Second attenuator 160…Second phase shifter 170...First synthesis circuit 180...Second synthesis circuit 200...Control unit 131, 132, 151, 182...attenuators 141, 142, 161…phase shifter 171, 172, 181…Synthesis circuit 210…ADC

Claims

1. an array antenna having a plurality of antenna elements; a branching unit that branches a received signal of each of the plurality of antenna elements into a first branch signal and a second branch signal; a first attenuation unit capable of changing a first attenuation amount of each of the first branch signals; a first phase shift unit capable of changing a first phase shift amount of each of the first branch signals; a second attenuation unit capable of changing a second attenuation amount of each of the second branch signals; a second phase shift unit capable of changing a second phase shift amount of each of the second branch signals; a first combining unit that combines the first branched signals that have passed through the first attenuation unit and the first phase shift unit to generate a first combined signal; a second combining unit that combines the second branched signals that have passed through the second attenuation unit and the second phase shift unit to generate a second combined signal; an optimization unit that, when optimizing a first weighting amount including the first attenuation amount and the first phase shift amount, sets a second attenuation amount corresponding to one or more antenna elements including one antenna element to zero, sets a second attenuation amount corresponding to antenna elements other than the one or more antenna elements to a maximum, and estimates a received signal of the one antenna element from the second composite signal; An antenna device comprising:

2. The one or more antenna elements are plural in number, The optimization unit is making the second phase shift amounts corresponding to the one or more antenna elements different from each other; 2. The antenna device according to claim 1.

3. The branching unit branches the received signal into two or more first branch signals and one second branch signal.

3. The antenna device according to claim 1 or 2.

4. the second combining unit includes a plurality of attenuators; The optimization unit is The attenuation of the attenuator through which the second branch signal from the one or more antenna elements passes is set to zero, and the attenuation of the other attenuators is set to maximum.

3. The antenna device according to claim 1 or 2.

5. The optimization unit is When optimizing the second weighting amount including the second attenuation amount and the second phase shift amount, a first attenuation amount corresponding to one or more antenna elements including one antenna element is set to zero, and a first attenuation amount corresponding to antenna elements other than the one or more antenna elements is set to a maximum, and a received signal of the one antenna element is estimated from the first composite signal.

3. The antenna device according to claim 1 or 2.

6. an array antenna having a plurality of antenna elements; a branching unit that branches a received signal from each of the plurality of antenna elements into a first branch signal and a second branch signal; a first attenuation unit capable of changing a first attenuation amount of each of the first branch signals; a first phase shift unit capable of changing a first phase shift amount of each of the first branch signals; a second attenuation unit capable of changing a second attenuation amount of each of the second branch signals; a second phase shift unit capable of changing a second phase shift amount of each of the second branch signals; a first combining unit that combines the first branched signals that have passed through the first attenuation unit and the first phase shift unit to generate a first combined signal; a second combining unit that combines the second branched signals that have passed through the second attenuation unit and the second phase shift unit to generate a second combined signal; An estimation method for an antenna device comprising: When optimizing the first weighting amount including the first attenuation amount and the first phase shift amount, a second attenuation amount corresponding to one or more antenna elements including one antenna element is set to zero, and a second attenuation amount corresponding to antenna elements other than the one or more antenna elements is set to a maximum, and a received signal of the one antenna element is estimated from the second composite signal. Estimation method.

7. an array antenna having a plurality of antenna elements; a splitter that splits a received signal from each of the plurality of antenna elements into a first branch signal and a second branch signal; a first attenuation unit capable of changing a first attenuation amount of a first branch signal; a first phase shift unit capable of changing a first phase shift amount of a first branched signal; a second attenuation unit capable of changing a second attenuation amount of the second branch signal; a second phase shift unit capable of changing a second phase shift amount of the second branched signal; a first combining unit that combines the first branched signals that have passed through the first attenuation unit and the first phase shift unit to generate a first combined signal; a second combining unit that combines the second branched signals that have passed through the second attenuation unit and the second phase shift unit to generate a second combined signal; A computer provided in the antenna device, a process of setting a second attenuation amount corresponding to one or more antenna elements including one antenna element to zero and setting a second attenuation amount corresponding to antenna elements other than the one or more antenna elements to a maximum value when optimizing a first weighting amount including the first attenuation amount and the first phase shift amount, and estimating a received signal of the one antenna element from the second composite signal. A program that executes the following.

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