Wireless communication system, wireless communication device, wireless communication method, and signal compensation program

Abstract

A wireless communication system according to an embodiment of the present invention compensates a processing target signal that is subjected to analog processing in a process for reception, by a reception device, of a signal which is sent using by a transmission device using radio waves, and performs wireless communication, wherein the reception device: receives weights and functional models sent by a transmission analog processing unit; respectively estimates, with the functional models, a plurality of factors that reduce the accuracy of analog processing of a processing target signal; calculates the respective weights of the plurality of factors with respect to a decrease in accuracy of the analog processing; uses the functional models to compensate the processing target signal on the basis of the respective weights of the received functional models and the calculated weights; calculates the respective weights of the plurality of factors with respect to a residual error remaining in the compensated signal; and performs compensation accompanied by machine learning with respect to the compensated processing target signal, on the basis of the calculated weights.

Description

[Technical Field]

[0001] The present invention relates to a wireless communication system, a wireless communication device, a wireless communication method, and a signal compensation program. [Background technology]

[0002] In wireless communications, for example, when quadrature modulation and demodulation are used, the received quadrature components I and Q may be affected by different interferences, resulting in signals with different attenuation and phase rotation (IQ imbalance).When IQ imbalance occurs, the quality of wireless communications deteriorates, so technology is needed to estimate and compensate for the phenomenon.

[0003] In addition to IQ imbalance, a technology has been proposed for wireless communication in which processed signals undergo analog processing in the process of receiving a signal transmitted by a transmitting device using radio waves, such as nonlinear distortion of an amplifier, carrier frequency offset, and phase noise (see, for example, Non-Patent Document 1).

[0004] Signals that are processed through analog processing often suffer from failures (device failures) due to analog device circuits in wireless communication devices. [Prior art documents] [Non-patent literature]

[0005] [Non-Patent Document 1] S. Fouladifard, H. Shafiee, “Frequency offset estimation in OFDM systems in presence of IQ imbalance,” ICCS, 2002, pp.214-218 Summary of the Invention [Problem to be solved by the invention]

[0006] However, in the past, when multiple device failures occurred, there was a problem that the compensation accuracy deteriorated when each individual event was estimated and compensated for. In other words, when multiple device failures occurred, residual errors could degrade the quality of wireless communication.

[0007] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a wireless communication system, a wireless communication device, a wireless communication method, and a signal compensation program that can accurately compensate for a processed signal that is analog-processed in the process of receiving a signal transmitted by a transmitting device using radio waves, even if multiple device failures occur in the processed signal. [Means for solving the problem]

[0008] A wireless communication system according to one embodiment of the present invention is a wireless communication system for wireless communication in which a processed signal that is analog-processed in a process in which a signal transmitted by a transmitting device using radio waves is received by a receiving device, the system comprising: a transmitting device; a first calculation unit that estimates, by a function model, each of a plurality of factors that reduce the accuracy of analog processing of the processed signal, and calculates a weight that each of the plurality of factors accounts for in the reduction in accuracy of the analog processing; and a transmitting analog processing unit that performs processing to transmit each of the function models and weights estimated by the first calculation unit; and a receiving device; a second calculation unit that estimates, using a function model, each of a plurality of factors that reduce the accuracy of analog processing of a signal, and calculates a weight that each of the plurality of factors accounts for in the reduction in accuracy of analog processing; a second compensation unit that compensates the processed signal using each of the function models based on each of the function models and weights received by the receiving analog processing unit and the weights calculated by the second calculation unit; a third calculation unit that calculates a weight that each of the plurality of factors accounts for in the residual error remaining in the signal compensated by the second compensation unit; and a third compensation unit that performs compensation involving machine learning on the processed signal compensated by the second compensation unit, based on the weights calculated by the third calculation unit.

[0009] Furthermore, a wireless communication device according to one embodiment of the present invention is a wireless communication device that performs wireless communication by compensating a processed signal that is analog-processed in the process of transmitting and receiving using radio waves, and is characterized by having: a receiving analog processing unit that receives a plurality of function models corresponding to a plurality of factors that reduce the accuracy of analog processing of the processed signal estimated by a first calculation unit provided in another wireless communication device, and the weights that each of the plurality of factors accounts for in the reduction in accuracy of the analog processing; a second calculation unit that estimates each of the plurality of factors that reduce the accuracy of analog processing of the processed signal using a function model and calculates the weights that each of the plurality of factors accounts for in the reduction in accuracy of the analog processing; a second compensation unit that compensates the processed signal using each of the function models based on each of the function models and weights received by the receiving analog processing unit and the weights calculated by the second calculation unit; a third calculation unit that calculates the weights that each of the plurality of factors accounts for in the residual error remaining in the signal compensated by the second compensation unit; and a third compensation unit that performs compensation involving machine learning on the processed signal compensated by the second compensation unit based on the weights calculated by the third calculation unit.

[0010] Furthermore, a wireless communication method according to one embodiment of the present invention is a method for wireless communication in which a processed signal that is analog-processed in a process in which a signal transmitted by a transmitting device using radio waves is received by a receiving device, and wireless communication is performed by compensating for the processed signal, the processed signal being analog-processed in the process of being received by a receiving device, the transmitting device performing a first calculation step of estimating, by a function model, each of a plurality of factors that reduce the accuracy of analog processing of the processed signal, and calculating a weight that each of the plurality of factors accounts for in the reduction in accuracy of analog processing, and a transmission analog processing step of transmitting each of the function models and weights estimated by the first calculation step, the receiving device performing a reception analog processing step of receiving each of the function models and weights transmitted by the transmission analog processing step, and a reception analog processing step of analog-processing the processed signal. a second calculation step of estimating each of a plurality of factors that reduce the accuracy of analog processing using a function model and calculating a weight that each of the plurality of factors accounts for in the reduction in accuracy of analog processing; a second compensation step of compensating the processed signal using each of the function models based on each of the function models and weights received by the receiving analog processing step and the weights calculated by the second calculation step; a third calculation step of calculating a weight that each of the plurality of factors accounts for in the residual error remaining in the signal compensated by the second compensation step; and a third compensation step of performing compensation involving machine learning on the processed signal compensated by the second compensation step based on the weights calculated by the third calculation step. [Effects of the Invention]

[0011] According to the present invention, even if multiple device failures occur in the processed signal, which is analog-processed in the process of receiving a signal transmitted by a transmitting device using radio waves, the processed signal can be accurately compensated. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a diagram illustrating an outline of the configuration of a wireless communication system. [Figure 2]FIG. 10 is a diagram illustrating a configuration including a compensation model of a wireless communication system that compensates for multiple device failures as a comparative example. [Figure 3] FIG. 1 is a diagram illustrating a schematic configuration including a compensation model of a wireless communication system that compensates for multiple device failures according to an embodiment. [Figure 4] 1 is a flowchart illustrating an example of an operation of a wireless communication system according to an embodiment. [Figure 5] FIG. 10 is a diagram illustrating a configuration overview of another form of a wireless communication system according to an embodiment. [Figure 6] FIG. 10 is a diagram illustrating a schematic configuration including a compensation model of a regenerative repeater station. [Figure 7] FIG. 1 is a diagram illustrating a schematic configuration including a compensation model of a receiving device. [Figure 8] FIG. 2 is a diagram illustrating an example of a hardware configuration of a receiving device according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0013] The configuration of a wireless communication system and a configuration for compensating for the quality of wireless communication will be described below with reference to the drawings. Figure 1 is a diagram showing an outline of the configuration of a wireless communication system.

[0014] 1, the wireless communication system is configured such that, for example, radio waves transmitted by a transmitting device (transmitting station) 1 are received by a receiving device (receiving station) 2. The wireless communication system performs wireless communication by compensating processed signals that are analog-processed in the process of receiving the signals transmitted by the transmitting device 1 using radio waves at the receiving device 2.

[0015] The transmitting device 1 has a transmission digital processing unit 10, a transmission analog processing unit 12, and an antenna 14. The transmission digital processing unit 10 performs digital processing for transmitting a signal. The transmission analog processing unit 12 performs analog processing for transmitting the signal, and transmits the signal via the antenna 14.

[0016] The transmission analog processing section 12 includes, for example, a quadrature modulation circuit 30, a frequency conversion circuit 32, and a power amplification circuit .

[0017] A device impairment of IQ imbalance may occur in the quadrature modulation circuit 30. A device impairment of phase noise may occur in the frequency conversion circuit 32. A device impairment of nonlinear distortion may occur in the power amplification circuit .

[0018] The receiving device 2 has an antenna 20, a reception analog processing unit 22, and a reception digital processing unit 24. The reception analog processing unit 22 receives a signal via the antenna 20 and performs analog processing, for example, to make the signal demodulatable. The reception digital processing unit 24 performs digital processing on the signal received by the reception analog processing unit 22.

[0019] The reception analog processing unit 22 includes, for example, a frequency conversion circuit 40 and a quadrature demodulation circuit 42. A device impairment such as phase noise may occur in the frequency conversion circuit 40. A device impairment such as IQ imbalance may occur in the quadrature demodulation circuit 42.

[0020] Furthermore, a fading channel exists when the receiving device 2 receives the signal transmitted by the transmitting device 1. Furthermore, a carrier frequency offset may occur between the frequency conversion circuit 32 and the frequency conversion circuit 40.

[0021] Therefore, at least one of the transmission digital processing unit 10 and the reception digital processing unit 24 estimates each device failure for each event and performs compensation for the device failure that may occur in a complex manner.

[0022] 2 is a diagram illustrating a comparative example of a configuration including a compensation model of a wireless communication system that compensates for multiple device failures. Hereinafter, the same reference numerals are used to designate components that are substantially the same as those described above.

[0023] The wireless communication system illustrated in FIG. 2 has two function models of device impairments that may occur in the transmitting device 1 and the receiving device 2 in order to perform one-to-one wireless communication in which the receiving device 2 performs compensation.

[0024] Here, G is a functional model representation of the device impairments of the analog devices, and H100 is a transfer function of the fading channel in the transmitter 1 and the receiver 2.

[0025] Specifically, the transmission analog processing unit 12 is provided with a function model (G TX,1 )50 and function model (G TX,2 ) 52 is set for the reception analog processing unit 22. RX,1 )60 and function model (G RX,2 )62 is set.

[0026] The reception digital processing unit 24 includes a first calculation unit 70 and a first compensation unit 72 .

[0027] The first calculation unit 70 estimates a plurality of factors that reduce the accuracy of analog processing of the processed signal using function models (function model 50, function model 52, H100, function model 60, function model 62), and calculates the weight (compensation weight) that each of the plurality of factors accounts for in the reduction in accuracy of analog processing.

[0028] The first compensating section 72 compensates the processed signal that is subjected to analog processing using each of the function models (function model 50, function model 52, H100, function model 60, function model 62) based on the weights calculated by the first calculating section 70.

[0029] In this case, if multiple device failures occur, the estimation accuracy of each function of the function model may deteriorate, making it impossible to calculate appropriate compensation weights, and residual errors may cause deterioration in wireless communication quality.

[0030] 3 is a diagram illustrating a configuration including a compensation model of a wireless communication system that compensates for multiple device failures according to an embodiment. In the wireless communication system illustrated in FIG. 3, the reception digital processing unit 24 includes a second calculation unit 74 and a second compensation unit 76 in addition to the first calculation unit 70 and first compensation unit 72 described above.

[0031] The second calculation unit 74 calculates the weights (compensation weights) that each of the multiple factors accounts for with respect to the residual error remaining in the signal compensated for by the first compensation unit 72.

[0032] The second compensation unit 76 performs compensation involving machine learning on the processed signal compensated for by the first compensation unit 72, based on the weights calculated by the second calculation unit 74 and the known signal. For example, the second compensation unit 76 performs compensation involving machine learning on the processed signal by at least one of linear compensation, compensation using a neural network, and nonlinear compensation using a nonlinear activation function. Note that the nonlinear compensation algorithm executed by the second compensation unit 76 is assumed to be arbitrary.

[0033] Next, an example of operation of the wireless communication system according to an embodiment will be described with reference to a flowchart of FIG.

[0034] As shown in FIG. 4, in step 100 (S100), the wireless communication system calculates the weights of the function model.

[0035] In step 102 (S102), the wireless communication system performs compensation using a function model.

[0036] In step 104 (S104), the wireless communication system calculates weights for nonlinear compensation. For example, the wireless communication system learns nonlinear compensation weights based on the compensation result using the function model, the estimated value of the function model, and the known signal so as to minimize the residual error.

[0037] In step 106 (S106), the wireless communication system performs nonlinear compensation for the residual error, for example, the wireless communication system performs the residual error compensation based on the compensation result using the function model and the nonlinear compensation weight.

[0038] In step 108 (S108), the wireless communication system performs digital processing such as demodulation.

[0039] Next, another embodiment of the wireless communication system will be described. Fig. 5 is a diagram showing the outline of the configuration of another embodiment of the wireless communication system according to an embodiment. As shown in Fig. 5, the other embodiment of the wireless communication system is configured such that, for example, a first-stage regenerative repeater station (relay station) 3a relays radio waves transmitted by a transmitting device (transmitting station) 1a so that a receiving device (receiving station) 2a receives the radio waves. The wireless communication system performs wireless communication by compensating the processed signal that is analog-processed in the process of receiving the signal transmitted by the transmitting device 1a using radio waves at the receiving device 2a.

[0040] The regenerative repeater station 3a has a function as a transmitting device and a function as a receiving device, and relays the signal transmitted by the transmitting device 1a to the receiving device 2a.

[0041] Furthermore, in the wireless communication system, the transmitting device 1a or the regenerative repeater station 3a transmits the estimated device impairment model and channel transfer function as auxiliary information (sub-information) to the subsequent regenerative repeater station 3a or receiving device 2a. The subsequent regenerative repeater station 3a or receiving device 2a is then configured to perform nonlinear compensation using the transmitted device impairment model and channel transfer function. Furthermore, the transmitting device 1a or the regenerative repeater station 3a may be configured to receive feedback of the auxiliary information when performing pre-compensation before transmitting a signal.

[0042] Fig. 6 is a diagram illustrating a schematic configuration including a compensation model of a regenerative repeater station 3a. The regenerative repeater station 3a illustrated in Fig. 6 includes a reception analog processing unit 22a, a digital processing unit 24a, and a transmission analog processing unit 26a.

[0043] The reception analog processing unit 22a receives a signal transmitted by, for example, the transmitting device 1a and performs analog processing, etc., to demodulate the signal. The digital processing unit 24a performs digital processing on the signal received by the reception analog processing unit 22a. The transmission analog processing unit 26a performs analog processing to transmit the signal digitally processed by the reception analog processing unit 22a to, for example, the receiving device 2a. For example, the transmission analog processing unit 26a performs processing to transmit each of the function models and weights estimated by the first calculation unit 70.

[0044] The analog reception processing unit 22a provided in the regenerative repeater station 3a receives, for example, each of the function models and weights transmitted by the transmitting device 1a.

[0045] The digital processing unit 24 a includes, for example, a first calculation unit 70 , a first compensation unit 72 , a demodulation / decoding unit 77 , an addition unit 78 , and a modulation / encoding unit 79 .

[0046] The demodulation / decoding unit 77 demodulates and decodes the signal compensated by the first compensation unit 72. The addition unit 78 adds the function models (function model 50, function model 52, H100, function model 60, function model 62) estimated by the first calculation unit 70 and weights (compensation weights) to the signal demodulated and decoded by the demodulation / decoding unit 77 and outputs the signal. The modulation / encoding unit 79 modulates and encodes the signal output by the addition unit 78.

[0047] Fig. 7 is a diagram illustrating a schematic configuration including a compensation model of a receiving device 2a. The receiving device 2a illustrated in Fig. 7 includes a receiving analog processing section 22a and a receiving digital processing section 24b.

[0048] The reception digital processing unit 24b includes a second calculation unit 80, a second compensation unit 82, an extraction unit 83, a third calculation unit 84, and a third compensation unit 85.

[0049] The second calculation section 80 estimates each of a plurality of factors that reduce the accuracy of analog processing of the processed signal using a function model, and calculates and outputs the weight that each of the plurality of factors accounts for in the reduction in accuracy of analog processing.

[0050] The second compensating section 82 compensates the processed signal using each of the function models based on the function models and weights received by the reception analog processing section 22a and the weights calculated by the second calculating section 80, and outputs the compensated signal.

[0051] The extracting unit 83 extracts the above-mentioned auxiliary information from the signal output by the second compensating unit 82 and outputs it to the third calculating unit 84 and the third compensating unit 85.

[0052] The third calculation unit 84 calculates the weights that each of multiple factors accounts for in the residual error remaining in the signal compensated by the second compensation unit 82, for example, using information output by the second calculation unit 80 and the extraction unit 83.

[0053] The third compensation unit 85 performs compensation involving machine learning on the processed signal compensated for by the second compensation unit 82, based on the weight calculated by the third calculation unit 84. For example, the third compensation unit 85 performs compensation involving machine learning on the processed signal by at least one of linear compensation, compensation using a neural network, and nonlinear compensation using a nonlinear activation function.

[0054] In one embodiment, the wireless communication system estimates and compensates for device failures using multiple function models. The wireless communication system may use any number of function models, or may use any number of function models.

[0055] Furthermore, the configuration of a wireless communication system according to one embodiment is not limited in its form, including the number of systems such as one-to-one communication, one-to-many communication, many-to-many communication, and multi-hop communication via relay stations (including regenerative relay / non-regenerative relay), antenna configurations such as SIMO / MIMO, and signal properties such as single-carrier / multi-carrier transmission.

[0056] In addition, in the wireless communication system according to an embodiment, the nonlinear compensation process may be performed by any wireless communication device, such as a transmitting station, a receiving station, or a relay station, and the number of wireless communication devices is not limited. Furthermore, the form of transmission of the sub-information is not limited to a method, and may be subcarriers, occupied packets / slots, power multiplexing, MIMO multiplexing, frequency multiplexing, or the like.

[0057] In this way, the wireless communication system of one embodiment performs compensation using machine learning even for residual errors remaining in the compensated signal, so that even if a complex device failure occurs in the processed signal that is analog-processed in the process of receiving the signal transmitted by the transmitting device using radio waves, the processed signal can be accurately compensated.

[0058] The first to third descriptions for the calculation unit and the compensation unit are merely descriptions indicating that they have different configurations within one wireless communication system.

[0059] Furthermore, each function possessed by the transmitting device 1 and the receiving devices 2, 2a may be partially or entirely configured by hardware such as a PLD (Programmable Logic Device) or an FPGA (Field Programmable Gate Array), or may be configured as a program executed by a processor such as a CPU.

[0060] For example, the receiving devices 2 and 2a can be realized using a computer and a program, and the program can be recorded on a storage medium or provided via a network.

[0061] Fig. 8 is a diagram showing an example of the hardware configuration of a receiving device 2a according to an embodiment. As shown in Fig. 8, the receiving device 2a has an input unit 90, an output unit 91, a communication unit 92, a CPU 93, a memory 94, and an HDD 95 connected via a bus 96, and has the functions of a computer. The receiving device 2a is also configured to be able to input and output data to and from a computer-readable storage medium 97.

[0062] The input unit 90 is, for example, a keyboard and a mouse, etc. The output unit 91 is, for example, a display device such as a display.

[0063] The communication unit 92 is a communication interface that performs wireless communication.

[0064] The CPU 93 controls each component of the receiving device 2a and performs predetermined processing, etc. The memory 94 and the HDD 95 are storage devices that store data, etc.

[0065] The storage medium 97 is capable of storing programs for executing the functions of the receiving device 2a, etc. The architecture configuring the receiving device 2a is not limited to the example shown in FIG. [Explanation of symbols]

[0066] 1,1a···Transmitting device, 2,2a···Receiving device, 3a···Regenerative relay station, 10···Transmitting digital processing unit, 12···Transmitting analog processing unit, 14···Antenna, 20···Antenna, 22,22a···Receiving analog processing unit, 24,24b···Receiving digital processing unit, 24a···Digital processing unit, 26a···Transmitting analog processing unit, 30···Quadrature modulation circuit, 32···Frequency conversion circuit, 34···Power amplifier circuit, 40···Frequency conversion circuit, 42···Quadrature demodulation circuit, 50,52,60,6 2 Function model, 70 First calculation unit, 72 First compensation unit, 74 Second calculation unit, 76 Second compensation unit, 77 Demodulation and decoding unit, 78 Addition unit, 79 Modulation and coding unit, 80 Second calculation unit, 82 Second compensation unit, 83 Extraction unit, 84 Third calculation unit, 85 Third compensation unit, 90 Input unit, 91 Output unit, 92 Communication unit, 93 CPU, 94 Memory, 95 HDD, 96 Bus, 97 Storage medium, 100 H (transfer function)

Claims

1. In a wireless communication system, a signal transmitted by a transmitting device using radio waves is analog-processed in a process for being received by a receiving device, and the signal is compensated for to perform wireless communication. The transmitting device a first calculation unit that estimates each of a plurality of factors that reduce the accuracy of analog processing of the processed signal using a function model and calculates a weight that each of the plurality of factors accounts for in the reduction of the accuracy of the analog processing; a transmission analog processing unit that performs processing to transmit each of the function models and weights estimated by the first calculation unit; and The receiving device a receiving analog processing unit that receives each of the function models and weights transmitted by the transmitting analog processing unit; a second calculation unit that estimates each of a plurality of factors that reduce the accuracy of analog processing of the processed signal using a function model and calculates a weight that each of the plurality of factors accounts for in the reduction of the accuracy of analog processing; a second compensation unit that compensates the processed signal using each of the function models based on the function models and weights received by the reception analog processing unit and the weights calculated by the second calculation unit; a third calculation unit that calculates a weight that each of the plurality of factors occupies with respect to a residual error remaining in the signal compensated by the second compensation unit; a third compensation unit that performs compensation involving machine learning on the processed signal compensated by the second compensation unit based on the weight calculated by the third calculation unit; A wireless communication system comprising:

2. The third compensation unit Compensating the processed signal with machine learning by at least one of linear compensation, compensation by a neural network, and nonlinear compensation using a nonlinear activation function.

2. The wireless communication system according to claim 1, wherein:

3. A wireless communication device that performs wireless communication by compensating a processed signal that is analog-processed in the process of transmitting and receiving using radio waves, a reception analog processing unit that receives a plurality of function models corresponding to a plurality of factors that reduce the accuracy of analog processing of the processed signal estimated by a first calculation unit included in the other wireless communication device, and weights that each of the plurality of factors occupies with respect to the reduction in accuracy of the analog processing; a second calculation unit that estimates each of a plurality of factors that reduce the accuracy of analog processing of the processed signal using a function model and calculates a weight that each of the plurality of factors accounts for in the reduction of the accuracy of analog processing; a second compensation unit that compensates the processed signal using each of the function models based on the function models and weights received by the reception analog processing unit and the weights calculated by the second calculation unit; a third calculation unit that calculates a weight that each of the plurality of factors occupies with respect to a residual error remaining in the signal compensated by the second compensation unit; a third compensation unit that performs compensation involving machine learning on the processed signal compensated by the second compensation unit based on the weight calculated by the third calculation unit; A wireless communication device comprising:

4. The third compensation unit Compensating the processed signal with machine learning by at least one of linear compensation, compensation by a neural network, and nonlinear compensation using a nonlinear activation function.

4. The wireless communication device according to claim 3,

5. A wireless communication method for wireless communication in which a processed signal undergoes analog processing in a process in which a signal transmitted by a transmitting device using radio waves is received by a receiving device, the method comprising: The transmitting device a first calculation step of estimating, by a function model, each of a plurality of factors that reduce the accuracy of analog processing of the processed signal, and calculating a weight that each of the plurality of factors accounts for in the reduction of the accuracy of analog processing; a transmission analog processing step for transmitting each of the function models and weights estimated in the first calculation step; and The receiving device a receiving analog processing step for receiving each of the function models and weights transmitted by the transmitting analog processing step; a second calculation step of estimating, by a function model, each of a plurality of factors that reduce the accuracy of analog processing of the processed signal, and calculating a weight that each of the plurality of factors accounts for in the reduction of the accuracy of analog processing; a second compensation step of compensating the processed signal using each of the function models based on the function models and weights received in the reception analog processing step and the weights calculated in the second calculation step; a third calculation step of calculating a weight that each of the plurality of factors occupies with respect to the residual error remaining in the signal compensated by the second compensation step; a third compensation step of performing compensation involving machine learning on the processed signal compensated in the second compensation step based on the weight calculated in the third calculation step; A wireless communication method comprising:

6. In the third compensation step, Compensating the processed signal with machine learning by at least one of linear compensation, compensation by a neural network, and nonlinear compensation using a nonlinear activation function.

6. The wireless communication method according to claim 5,

7. A signal compensation program for causing a computer to function as each unit of the wireless communication device according to claim 3 or 4.

Images