JP2017028363A - Transmission reception device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transmission reception device which can improve a removal performance by generating a signal removing a sneak self-interference signal from an input signal in a high accuracy even when receiving random time fluctuation of the sneak self-interference signal in the transmission reception device.SOLUTION: A transmission reception device that simultaneously sends and receives radio wave at the same frequency bandwidth comprises: a detector which generates a replica signal of a transmitter signal using a time fluctuation component of the transmitter signal and an input signal that are sent and received to detect a time when a sneak self-interference signal arrives; a cancel unit which generates a reference signal using the replica signal of the transmitter signal, the extracted time fluctuation component, and the detected time to compare the reference signal with the sneak self-interference signal, and generates a replica signal of the sneak self-interference signal from the reference signal using difference information indicating difference of amplitude and phase between the reference signal and the sneak self-interference signal to remove the sneak self-interference signal from the input signal; and a determination unit which compares a residual component of the sneak self-interference signal with a threshold value to determine whether the sneak self-interference signal is removed from the input signal or not.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a transceiver that performs simultaneous transmission and reception of radio waves in the same frequency band.

  In recent years, with the development of wireless communication systems such as mobile phones and wireless LANs, frequency demand has increased, and in order to improve frequency utilization efficiency, a technique for performing simultaneous transmission and reception using the same frequency has been proposed.

  In this technique, the reception antenna receives a transmission signal (hereinafter also referred to as a wraparound self-interference signal) that has wrapped around with a very high power, and thus it is necessary to remove the wraparound self-interference signal with high accuracy. For example, using a known transmission signal, the timing, amplitude, and phase of the wraparound self-interference signal are estimated, the transmission signal is branched in the transmitter / receiver, and adjusted to the same level as the delay unit that matches the timing with the wraparound self-interference signal. Techniques have been proposed in which anti-phase synthesis is performed using an attenuator, a phase shifter for phase matching, and a multiplexer to remove a wraparound self-interference signal (see, for example, Non-Patent Documents 1 and 2).

  Also, using known transmission signals, the timing and channel characteristics of the sneaking self-interference signal are estimated, a separate transmission processing unit with the same configuration is prepared separately, and the sneaking self-interference signal is generated by the predistortion technique, and the anti-phase synthesis is performed. Thus, a technique for removing the sneaking self-interference signal has been proposed (see, for example, Non-Patent Document 3).

D. Korpi, et. Al., "Widely Linear Digital Self-Interference Cancellation in Direct-Conversion Full-Duplex Transceiver", IEEE Journal on Selected Areas in Communications, vol.32, no.9, pp.1674-1687, Sept . 2014 V. Syrjala, et. Al., "Analysis of oscillator phase-noise effects on self-interference cancellation in full-duplex OFDM radio transceivers", IEEE Transactions on Wireless Communications, vol.13, no.6, pp.2977-2990 , June 2014 R. Askar, et. Al., "Active self-interference cancellation mechanism for full-duplex wireless transceivers", 9th International Conference on Cognitive Radio Oriented Wireless Networks and Communications (CROWNCOM) 2014. pp.539-544, June 2014

  However, in Non-Patent Documents 1 and 2, it is necessary to set the timing, amplitude, and phase with high precision. However, if the sneaking self-interference signal undergoes random fluctuations in the transmission / reception circuit, the estimation error is large. There is a problem that the residual component of the self-interference signal that is sneaking around remains superimposed.

  Further, in Non-Patent Document 3, since a self-interference signal is generated by using a predistortion technique, there is a time difference between the time when the parameter is estimated and the time when the canceling process is performed. There is a problem of becoming.

  The present invention can generate a signal for removing a wraparound self-interference signal from a received signal with high accuracy even when the wraparound self-interference signal is subject to random fluctuations in the transceiver, and can improve the removal performance. An object is to provide a transceiver.

  A first invention is a transceiver that performs simultaneous transmission and reception of radio waves in the same frequency band, using an extraction unit that extracts time-varying components of transmission signals and reception signals transmitted and received by the transceiver, and using the extracted time-varying components A first generation unit that generates a replica signal that is a replica of the transmission signal, and the received time of the arriving self-interference signal that the transmission signal of the own device wraps around among the signals included in the reception signal. Using the detection unit to detect, the replica signal of the transmission signal, the extracted time-varying component, and the detected time, compare the reference signal with the wraparound self-interference signal, and reference A difference information indicating a difference in amplitude and phase between the signal and the wraparound self-interference signal is obtained, and a replica signal that is a replica of the wraparound self-interference signal is generated from the reference signal using the obtained difference information. And a cancellation unit that removes the wraparound self-interference signal from the received signal using a replica signal of the wraparound self-interference signal, and a residual component of the wraparound self-interference signal that remains in the received signal from which the wraparound self-interference signal has been removed. And a determination unit that compares the threshold value and determines whether or not the wraparound self-interference signal has been removed from the reception signal output from the cancellation unit.

  According to a second aspect of the invention, the extraction unit includes a phase noise of the first local oscillation signal or the first local oscillation signal used for frequency conversion or modulation of the transmission signal, and a first clock used for digital-analog conversion of the transmission signal. The clock jitter of the signal or the first clock signal, the phase noise of the second local oscillation signal or the second local oscillation signal used for the conversion or demodulation of the frequency of the reception signal, and the second used for the analog-digital conversion of the reception signal. One or more components are extracted from the time variation component of the clock signal or the clock jitter of the second clock signal.

  A third invention includes an automatic gain control unit that automatically adjusts a gain for a received signal, and the extraction unit extracts gain information of a gain controlled by the automatic gain control unit as a time-varying component. To do.

  A fourth invention is a transceiver that performs simultaneous transmission and reception of radio waves in the same frequency band, using an extraction unit that extracts time-varying components of transmission signals and reception signals that are transmitted and received by the transceiver, and using the extracted time-varying components A first generation unit that generates a replica signal that is a replica of the transmission signal, and the received time of the arriving self-interference signal that the transmission signal of the own device wraps around among the signals included in the reception signal. Using the detection unit to detect, the replica signal of the transmission signal, the extracted time-varying component, and the detected time, compare the reference signal with the wraparound self-interference signal, and reference A comparison unit that obtains difference information indicating a difference in amplitude and phase between the signal and the wraparound self-interference signal, and a replica signal that is a replica of the wraparound self-interference signal is generated from the transmission signal using the difference information A third generation unit, a cancellation unit that removes the wraparound self-interference signal from the received signal using a replica signal of the wraparound self-interference signal, and a residual sneak self-interference signal remaining in the received signal from which the wraparound self-interference signal has been removed And a determination unit that compares the component with a threshold value and determines whether or not the wraparound self-interference signal has been removed from the reception signal output from the cancellation unit.

  A fifth invention is a transceiver that performs simultaneous transmission and reception of radio waves in the same frequency band, an extraction unit that extracts a time-varying component of a received signal received by the transceiver, and a transmission signal using the extracted time-varying component A first generation unit that generates a replica signal that is a replica of the received signal, and a detection that uses the received signal to detect the arrival time of the wraparound self-interference signal that the transmission signal of the own device wraps around among the signals included in the received signal The second generation unit that generates the reference signal, the reference signal and the wraparound self-interference signal, and the reference signal and the wraparound A third generation unit that obtains difference information indicating a difference in amplitude and phase from the self-interference signal, and generates a replica signal that is a replica of the self-interference signal from the reference signal using the obtained difference information; Using the replica signal of the wraparound self-interference signal, the cancel unit that removes the wraparound self-interference signal from the received signal and the residual component of the wraparound self-interference signal remaining in the received signal from which the wraparound self-interference signal has been removed are compared with the threshold value. And a determination unit for determining whether or not the sneak self-interference signal has been removed from the reception signal output from the cancellation unit.

  According to a sixth aspect of the present invention, the extraction unit includes a local oscillation signal used for frequency conversion or demodulation of the received signal or phase noise of the local oscillation signal and a clock signal used for analog-digital conversion of the received signal or a clock of the clock signal. It is characterized in that at least one of time-varying components with jitter is extracted.

  A seventh invention includes an automatic gain control unit that automatically adjusts a gain for a received signal, and the extraction unit extracts gain information of a gain controlled by the automatic gain control unit as a time-varying component. To do.

  The present invention can generate a signal for removing a wraparound self-interference signal from a received signal with high accuracy even when the wraparound self-interference signal is subject to random fluctuations in the transceiver, and can improve the removal performance. .

It is a figure which shows one Embodiment of a transmitter / receiver. It is a figure which shows an example of the time fluctuation component extraction part shown in FIG. It is a figure which shows an example of the transmission / reception process in the transmitter / receiver shown in FIG. It is a figure which shows another embodiment of a transmitter / receiver. It is a figure which shows an example of the transmission / reception process in the transmitter / receiver shown in FIG. It is a figure which shows another embodiment of a transmitter / receiver. It is a figure which shows an example of the transmission / reception process in the transmitter / receiver shown in FIG. It is a figure which shows another embodiment of a transmitter / receiver.

  Hereinafter, embodiments will be described with reference to the drawings.

  FIG. 1 illustrates one embodiment of a transceiver.

  The transceiver 150 illustrated in FIG. 1 includes a transmission unit 10, a reception unit 40, a local oscillator 50, a clock generator 60, a time variation component extraction unit 70, a control unit 80, and a cancellation unit 90.

  The transmission unit 10 includes a DAC (Digital to Analog Converter) 11, a mixer 12, and a PA (Power Amplifier) 13. The transmission unit 10 is connected to the transmission antenna 20 and transmits a transmission signal via the transmission antenna 20.

  The DAC 11 performs analog transmission of a digital transmission signal including data modulated by a modulation method such as QPSK (Quadrature Phase Shift Keying) by a modulator included in the transmission unit 10 based on a clock signal output from the clock generator 60. Convert to signal.

  The mixer 12 up-converts an analog transmission signal (that is, a baseband signal) including data to an RF (Radio Frequency) band frequency of a LO (Local) signal output from the local oscillator 50.

  The PA 13 amplifies the power of the generated transmission signal.

  The receiving unit 40 is connected to the receiving antenna 30 and receives a transmission signal transmitted from another transceiver via the receiving antenna 30. In addition, the receiver 40 receives the transmission signal transmitted by the transmitter 10 as a wraparound self-interference signal that wraps around the reception antenna 30 because the transceiver 150 performs simultaneous transmission and reception of the same frequency band. The receiving unit 40 includes an LNA (Low Noise Amplifier) 41, a mixer 42, an AGC (Automatic Gain Control) 43, and an ADC (Analog to Digital Converter) 44.

  The LNA 41 is a low noise amplifier, and amplifies the reception signal received via the reception antenna 30.

  The mixer 42 down-converts from the frequency of the RF band to the frequency of the baseband signal using the LO signal output from the local oscillator 50. The mixer 42 outputs a baseband reception signal including data to the AGC 43.

  The AGC 43 controls the power level of the received signal so that the power of the received baseband received signal is within a predetermined range, and outputs the controlled received signal to the ADC 44. In addition, the AGC 43 outputs a signal including gain information indicating the content of gain control performed on the received signal to the time variation component extraction unit 70. Note that the receiving unit 40 may not have the AGC 43.

  The ADC 44 converts the baseband received signal into a digital signal based on the clock signal output from the clock generator 60. Then, the reception unit 40 outputs the reception signal converted into the digital signal to the control unit 80 and the cancellation unit 90, respectively.

  The baseband signals described above may be IF (Intermediate Frequency) band signals (the same applies to the subsequent basebands).

  The local oscillator 50 is an oscillator such as a VCO (Voltage-Controlled Oscillator), and generates an LO signal having a predetermined frequency by controlling an oscillation frequency according to an applied voltage. The local oscillator 50 outputs the generated LO signal to the mixers 12 and 42 and the time variation component extraction unit 70. The transceiver 150 is provided with two local oscillators 50, one local oscillator 50 outputs a LO signal to the mixer 12 of the transmitter 10, and the other local oscillator 50 outputs a LO signal to the mixer 42 of the receiver 40. It may be.

  The clock generator 60 generates a clock signal that operates the DAC 11 and the ADC 44. The clock generator 60 outputs the generated clock signal to each of the DAC 11, the ADC 44 and the time variation component extraction unit 70.

  The time variation component extraction unit 70 extracts time variation components such as amplitude and phase in transmission signals and reception signals transmitted and received by the transceiver 150. For example, the time variation component extraction unit 70 receives signals of the AGC 43, the local oscillator 50, and the clock generator 60 as time variation components such as amplitude and phase in the transmission signal and the reception signal, respectively. Then, the time variation component extraction unit 70 samples signals received from each of the AGC 43, the local oscillator 50, and the clock generator 60 using the ADC included in the time variation component extraction unit 70, and controls each sampled signal. To the unit 80. The operation of the time variation component extraction unit 70 will be described with reference to FIG.

  The control unit 80 is a processor or the like, and controls each element of the transceiver 150 by executing a program stored in a storage device such as a memory included in the transceiver 150. Further, the control unit 80 operates as the replica generation unit 81 and the determination unit 82 by executing the program.

  The replica generation unit 81 refers to the transmission signal in the digital domain. Further, the replica generation unit 81 acquires the time variation component of the amplitude and phase of the transmission signal extracted by the time variation component extraction unit 70 (that is, the LO signal of the local oscillator 50, the clock signal of the clock generator 60, and the like). The replica generation unit 81 changes the amplitude and phase of the digital transmission signal received using the acquired time-varying component, and the replica signal of the transmission signal subjected to pseudo processing of the DAC 11 and the mixer 12 of the transmission unit 10 Is generated.

  In addition, the replica generation unit 81 uses the reception signal received from the reception unit 40 to detect the arrival time of the wraparound self-interference signal that the transmission signal has circulated through the reception antenna 30. For example, the replica generation unit 81 compares the power of the reception signal received from the reception unit 40 with a predetermined value, and detects the time when the self-interference signal arrives at the time when the predetermined value is exceeded. Alternatively, the replica generation unit 81 performs correlation processing between the generated replica signal of the transmission signal and the reception signal received from the reception unit 40, and detects the time when the self-interference signal arrives around the time when the correlation value shows a peak. May be. Then, for example, the replica generation unit 81 obtains the propagation time from when the transmission unit 10 transmits the transmission signal until the reception unit 40 receives the self-interference signal. The propagation time is, for example, the sum of the passage times between the input and output of the transmission unit 10 and the reception unit 40 measured in advance according to the RF to be used, between the input time to the transmission unit 10 and the output time of the reception unit 40. It is calculated as the time subtracted from the time.

  The replica generation unit 81 detects the time-varying components of the amplitude and phase of the received signal extracted by the time-varying component extraction unit 70 at the timing of the detected time (that is, signals of the AGC 43, the local oscillator 50, and the clock generator 60). Is used to generate a replica signal of the self-interference signal. For example, the replica generation unit 81 uses the obtained time variation components of the signals of the AGC 43, the local oscillator 50, and the clock generator 60 to change the amplitude and phase of the replica signal of the transmission signal generated by calculation or the like. Generate a signal. The replica generation unit 81 compares the generated reference signal with the wraparound self-interference signal included in the reception signal received from the reception unit 40, and compares the relative amplitude and phase between the reference signal and the wraparound self-interference signal. Is obtained. And the replica production | generation part 81 produces | generates the replica signal of a self-interference signal by changing the amplitude and phase of a reference signal using the calculated | required difference information. The replica generation unit 81 outputs the generated replica signal of the wraparound self-interference signal to the cancellation unit 90.

  The determination unit 82 measures the remaining amount of the wraparound self-interference signal remaining in the reception signal from the received signal power in the reception signal from which the wraparound self-interference signal has been removed by the cancel unit 90. For example, in the training period in which the replica generation unit 81 obtains the time of arrival of the wraparound self-interference signal and the difference information necessary for generating the replica signal of the wraparound self-interference signal, the transceiver 150 transmits the transmission signal including predetermined data. (Training signal) is transmitted. In other words, during the training period, the transceiver 150 does not receive any signals other than the transmitted self-interference signal of the training signal. Therefore, the determination unit 82 can measure the power of the received signal received from the cancel unit 90, that is, the power of the remaining sneak self-interference signal as a residual error. Then, the determination unit 82 determines whether or not the measured residual error value is equal to or less than the training period threshold value. The threshold for the training period is a threshold set by the control unit 80 in the determination unit 82 during the training period, and is set based on the noise level and the allowable power of the remaining sneak self-interference signal.

  The determination unit 82 determines that the wraparound self-interference signal has been removed by the cancel unit 90 when the residual error value is equal to or less than the training period threshold value. In this case, the control unit 80 stores the propagation time and the difference information obtained from the time when the detected wraparound self-interference signal arrives in the storage device of the transceiver 150. On the other hand, when the value of the residual error is larger than the training period threshold, the determination unit 82 determines that the wraparound self-interference signal is not sufficiently removed from the received signal. In this case, the control unit 80 adjusts the time at which the wraparound self-interference signal arrives by executing an optimization algorithm such as an LMS (Least Mean Squares) algorithm so that the residual error value is minimized. Then, the control unit 80 repeatedly adjusts until the value of the residual error becomes equal to or less than the training period threshold (that is, the wraparound self-interference signal is removed by the cancel unit 90).

  And the control part 80 transfers to normal operation of simultaneous transmission / reception after a training period is complete | finished. The replica generation unit 81 transmits and receives the time-varying component of the transmission signal and the reception signal extracted by the time-varying component extraction unit 70 at the time when the wraparound self-interference signal arrives using the propagation time obtained in the training period, and transmission / reception Using the difference information held in the storage device of the machine 150, a replica signal of the wraparound self-interference signal is generated as needed.

  Note that, even during the normal operation period, the control unit 80 causes the determination unit 82 to measure the residual error of the self-interference signal, and compares the measured residual error value with the normal operation threshold value. If it is larger than the operation threshold, the training period may be resumed. The normal operation threshold value is a threshold value set by the control unit 80 in the determination unit 82 during the normal operation period, and is the power received from other transceivers and the power of the remaining sneak self-interference signal allowed. Set based on. In addition, the control unit 80 causes the determination unit 82 to measure an error rate such as a bit error rate or a packet error rate of a received signal received from another transceiver instead of the determination based on the residual error, and the measured error rate is predetermined. When it deteriorates from the value, it may be returned to the training period. Further, the control unit 80 may start from the training period every time the transceiver 150 is activated. Moreover, you may make it return to a training period with a predetermined period.

  The cancellation unit 90 removes the wraparound self-interference signal included in the received signal using the replica signal of the wraparound self interference signal generated by the replica generation unit 81. For example, the cancel unit 90 synthesizes the replica signal of the wraparound self-interference signal received from the replica generation unit 81 at the timing of the arrival of the wraparound self-interference signal with the reception signal in reverse phase, and Remove interference signals. The cancel unit 90 outputs the received signal from which the wraparound self-interference signal has been removed to the determination unit 82. In addition, the transceiver 150 performs demodulation processing on the received signal from which the wraparound self-interference signal has been removed by the cancel unit 90.

  FIG. 2 shows an example of the time variation component extraction unit 70 shown in FIG. The time variation component extraction unit 70 illustrated in FIG. 2A includes three ADCs 71, 72, and 73. The ADC 71 samples the signal including the gain information received from the AGC 43 and outputs the sampled gain information to the control unit 80. Note that when the AGC 43 can output gain information as digital data, the ADC 71 is unnecessary. The ADC 72 samples the LO signal generated by the local oscillator 50 and outputs the sampled LO signal to the control unit 80. The ADC 73 samples the clock signal generated by the clock generator 60 or the clock jitter of the clock signal, and outputs the sampled clock signal or clock jitter to the control unit 80. The ADCs 71, 72, and 73 are driven using a clock signal from a clock generator different from the clock generator 60.

  For example, the gain information received from the AGC 43 includes a time variation component related to the amplitude in the received signal. The LO signal of the local oscillator 50 includes a time variation component related to the amplitude and phase in the transmission signal and the reception signal. The clock signal or clock jitter of the clock generator 60 includes a time variation component related to the amplitude and phase in the transmission signal and the reception signal.

  FIG. 2B shows another example of the time variation component extraction unit 70 shown in FIG. The same or similar elements as those described in FIG. 2A are denoted by the same or similar reference numerals, and detailed description thereof will be omitted.

  The time variation component extraction unit 70 illustrated in FIG. 2B extracts the phase noise of the LO signal instead of the amplitude of the LO signal. Therefore, the time variation component extraction unit 70 further includes a delay unit 74, a 90-degree phase shifter 75, a mixer 76, and an LPF (Low-Pass Filter) 77. The time variation component extraction unit 70 distributes the LO signal from the local oscillation signal 50 to the delay unit 74 and the 90 degree phase shifter 75. Delay device 74 delays the received LO signal so that it is input to mixer 76 at the same timing as the LO signal from 90-degree phase shifter 75. On the other hand, the 90 degree phase shifter 75 changes the phase of the received LO signal by 90 degrees. The mixer 76 mixes the LO signal from the delay unit 74 and the LO signal from the 90 degree phase shifter 75. Then, by passing the signal output from the mixer 76 through the LPF 77, a signal indicating the amount of change in phase noise is output from the LPF 77. The time variation component extraction unit 70 extracts the phase noise by sampling the signal output from the LPF 77 using the ADC 72. When the LO signal of the local oscillator 50 has a high frequency such as a millimeter wave band, the time variation component extraction unit 70 uses an ADC having a lower sampling rate to sample phase noise than to sample the LO signal. And cost can be reduced.

  Further, the time variation component extraction unit 70 may hold the signals of the AGC 43, the local oscillator 50 and the clock generator 60 in the storage device of the transceiver 150. Thereby, the control unit 80 reads out the time-varying components of the transmission signal and the reception signal from the storage device of the transceiver 150 at a desired timing at which the cancellation unit 90 removes the self-interference signal included in the reception signal. A replica of the interference signal can be generated.

  In addition, the time variation component of the transmission signal and the reception signal extracted by the time variation component extraction unit 70 may not include the gain information of the AGC 43 when the transceiver 150 does not have the AGC 43.

  FIG. 3 shows an example of transmission / reception processing in the transceiver 150 shown in FIG. The processing illustrated in FIG. 3 is realized, for example, when a control unit 80 such as a processor included in the transceiver 150 executes a program stored in the storage device. Note that the processing illustrated in FIG. 3 may be executed by hardware provided in the transceiver 150. In this case, the replica generation unit 81 and the determination unit 82 illustrated in FIG. 1 are realized by a circuit arranged in the transceiver 150.

  In step S <b> 100, the transmission unit 10 transmits a training signal including predetermined data via the transmission antenna 20 based on an instruction from the control unit 80 in the training period.

  In step S110, the time variation component extraction unit 70 extracts time variation components such as amplitude and phase in the transmission signal (that is, the training signal) and the reception signal (that is, the wraparound self-interference signal of the training signal) transmitted and received by the transceiver 150. . For example, as shown in FIG. 2, the time variation component extraction unit 70 receives signals from the AGC 43, the local oscillator 50, and the clock generator 60 as time variation components of amplitude and phase in the transmission signal and the reception signal, respectively. Then, the time variation component extraction unit 70 samples a signal received from each of the AGC 43, the local oscillator 50, and the clock generator 60 using the ADC included in the time variation component extraction unit 70, and outputs the sampled signal to the control unit 80.

  When the transceiver 150 includes two local oscillators 50, the time variation component extraction unit 70 may acquire the LO signal of each local oscillator 50 as a time variation component in the transmission signal and the reception signal.

  In step S120, the replica generation unit 81 performs time-varying components of the digital transmission signal (training signal) including data and the amplitude and phase of the transmission signal extracted in step S110 (that is, the LO signal and clock of the local oscillator 50). A replica signal of the transmission signal transmitted by the transmission unit 10 is generated using the clock jitter of the generator 60).

  In step S <b> 130, the replica generation unit 81 uses the reception signal received by the reception unit 40 to detect the arrival time of the wraparound self-interference signal that the transmission signal has circulated through the reception antenna 30. And the replica production | generation part 81 calculates | requires the propagation time after the transmission part 10 transmits a transmission signal until the receiving part 40 wraps around and receives an own interference signal.

  In step S140, the replica generation unit 81 uses the time variation component extracted by the time variation component extraction unit 70 at the timing of the time detected in step S130 or the timing adjusted in step S190 described later, and transmits the transmission signal. The reference signal is generated by changing the amplitude and phase of the replica signal.

  In step S150, the replica generation unit 81 compares the reference signal generated in step S140 with the wraparound self-interference signal included in the reception signal received by the reception unit 40, and between the reference signal and the wraparound self-interference signal. Difference information indicating a relative amplitude and phase difference is obtained.

  In step S160, the replica generation unit 81 changes the amplitude and phase of the reference signal using the difference information obtained in step S150, and generates a replica signal of the wraparound self-interference signal. Then, the replica generation unit 81 outputs the generated replica signal of the wraparound self-interference signal to the cancellation unit 90.

  In step S170, the cancellation unit 90 removes the wraparound self-interference signal included in the received signal using the replica signal of the wraparound self-interference signal generated in step S160.

  In step S180, the determination unit 82 measures the power of the received signal from which the wraparound self-interference signal has been removed in step S170 as a residual error.

  In step S190, the determination unit 82 determines whether the residual error value measured in step S180 is equal to or less than a training period threshold value. The determination unit 82 determines that the wraparound self-interference signal has been removed from the received signal when the measured residual error value is less than or equal to the training period threshold. Then, the control unit 80 stores in the storage device of the transceiver 150 the time when the wraparound self-interference signal arrives and the propagation time and difference information obtained from the time of arrival. In this case, the processing of the transceiver 150 ends the training period (that is, the processing shown in FIG. 3) and moves to normal operation.

  On the other hand, when the value of the residual error is larger than the training period threshold, the determination unit 82 determines that the wraparound self-interference signal is not sufficiently removed from the received signal. Then, the control unit 80 adjusts the time at which the wraparound self-interference signal arrives by executing an optimization algorithm such as an LMS algorithm so that the residual error value is minimized. In this case, the processing of the transceiver 150 proceeds to step S140.

  As described above, in the embodiment shown in FIGS. 1 to 3, the replica generation unit 81 performs time-varying components of amplitude and phase in the transmission signal and reception signal extracted by the time-varying component extraction unit 70 (that is, AGC 43, local oscillator). 50 and the clock generator 60), a replica signal of the wraparound self-interference signal is generated. As a result, the transmitter / receiver 150 can generate a signal for removing the wraparound self-interference signal from the received signal with high accuracy even when the wraparound self-interference signal is subject to fluctuations in the transceiver 150 when there is randomness. The transceiver 150 can improve the performance of removing the sneaking self-interference signal.

  FIG. 4 shows another embodiment of a transceiver. The same or similar elements as those described in FIG. 1 are denoted by the same or similar reference numerals, and detailed description thereof will be omitted.

  The transceiver 150A illustrated in FIG. 4 includes a transmission unit 10, a reception unit 40, a local oscillator 50, a clock generator 60, a time variation component extraction unit 70, a control unit 80a, a replica generation circuit 100, and a cancellation unit 110.

  The control unit 80a is a processor or the like, and controls each element of the transceiver 150A by executing a program stored in a storage device such as a memory included in the transceiver 150A. The control unit 80a operates as a replica generation unit 81a and a determination unit 82 by executing a program.

  Similar to the replica generation unit 81 illustrated in FIG. 1, the replica generation unit 81 a receives a digital transmission signal including data. In addition, the replica generation unit 81a generates time variation components that give time variation to the amplitude and phase of the transmission signal extracted by the time variation component extraction unit 70 (that is, the LO signal of the local oscillator 50 and the clock jitter of the clock generator 60). get. The replica generation unit 81a changes the amplitude and phase of the digital transmission signal received using the acquired time-varying component, and the replica signal of the transmission signal subjected to pseudo processing of the DAC 11 and the mixer 12 of the transmission unit 10 Is generated.

  Similarly to the replica generation unit 81 illustrated in FIG. 1, the replica generation unit 81 a uses the reception signal received by the reception unit 40 to generate a wraparound self-interference signal that has been transmitted through the reception antenna 30. Detect the time of arrival. Note that when the replica generation unit 81a detects the time when the wraparound self-interference signal arrives, it is preferable that the control unit 80a temporarily stops the operations of the replica generation circuit 100 and the cancellation unit 110. The control unit 80a preferably restarts the operations of the replica generation circuit 100 and the cancellation unit 100 after the replica generation unit 81a detects the time when the self-interference signal arrives. Thereafter, the replica generation unit 81a obtains, for example, a propagation time from when the transmission unit 10 transmits a transmission signal to when the reception unit 40 wraps around and receives the own interference signal.

  Similar to the replica generation unit 81 shown in FIG. 1, the replica generation unit 81 a uses the time variation component of the amplitude and phase in the received signal extracted by the time variation component extraction unit 70 at the timing of the detected time, and uses the reference signal Is generated. The replica generation unit 81a compares the generated reference signal with the wraparound self-interference signal included in the reception signal received by the reception unit 40, and compares the relative amplitude and phase between the reference signal and the wraparound self-interference signal. Is obtained. Then, the control unit 80a outputs the propagation time and the difference information obtained by the replica generation unit 81a to the replica generation circuit 100 at the timing of the detected time.

  The replica generation circuit 100 uses the propagation time and difference information received from the control unit 80a, delays the transmission signal received from the transmission unit 10 by the propagation time, changes the amplitude and phase, and converts the analog signal of the wraparound self-interference signal. Generate a replica signal. The replica generation circuit 100 outputs the generated replica signal of the wraparound self-interference signal to the cancel unit 110.

  The cancellation unit 110 removes the wraparound self-interference signal included in the received signal using the replica signal of the wraparound self interference signal generated by the replica generation circuit 100. For example, the cancel unit 110 combines the replica signal of the wraparound self-interference signal with the reception signal received via the reception antenna 30 in the opposite phase, and removes the wraparound self-interference signal included in the reception signal. The cancel unit 110 outputs the reception signal from which the wraparound self-interference signal has been removed to the reception unit 40.

  FIG. 5 shows an example of transmission / reception processing in the transceiver 150A shown in FIG. The processing illustrated in FIG. 5 is realized, for example, when a control unit 80a such as a processor included in the transceiver 150A executes a program stored in the storage device. Note that the processing illustrated in FIG. 5 may be executed by hardware provided in the transceiver 150A. In this case, the replica generation unit 81a and the determination unit 82 illustrated in FIG. 4 are realized by a circuit disposed in the transceiver 150A.

  Note that among the operations of the steps shown in FIG. 5, those showing the same or similar processing as the steps shown in FIG. 3 are given the same step numbers, and detailed descriptions thereof are omitted.

  The transceiver 150A executes the process of step S155 after executing the process of steps S100 to S150 shown in FIG.

  In step S155, the control unit 80a obtains the propagation time and difference information obtained in each of step S130 and step S150 at the timing of the arrival of the wraparound self-interference signal detected in step S130. Output to.

  In step S160a, the replica generation circuit 100 uses the propagation time and the difference information received from the control unit 80a, delays the transmission signal received from the transmission unit 10 by the propagation time, changes the amplitude and phase, and causes wraparound self-interference. Generate an analog replica signal of the signal. The replica generation circuit 100 outputs the generated replica signal of the wraparound self-interference signal to the cancel unit 110.

  In step S170a, the cancellation unit 110 removes the wraparound self-interference signal included in the received signal using the replica signal of the wraparound self-interference signal generated in step S160a.

  The transceiver 150A executes the process of step S170a, and then executes the process of step S180 and step S190.

  As described above, in the embodiment shown in FIG. 4 and FIG. 5, the replica generation unit 81a performs the time variation component of amplitude and phase in the transmission signal and the reception signal extracted by the time variation component extraction unit 70 (that is, AGC 43, local oscillator). 50 and the clock generator 60) to generate a reference signal. The replica generation unit 81a compares the generated reference signal with the wraparound self-interference signal included in the reception signal received by the reception unit 40, and compares the relative amplitude and phase between the reference signal and the wraparound self-interference signal. Is obtained. Then, the replica generation circuit 100 uses the propagation time and the difference information received from the control unit 80a, delays the transmission signal received from the transmission unit 10 by the propagation time, changes the amplitude and phase, and generates the wraparound self-interference signal. Generate a replica signal.

  Thereby, the transmitter / receiver 150A can generate a signal for removing the wraparound self-interference signal from the received signal with high accuracy even when the wraparound self-interference signal is subject to fluctuations in the transceiver 150A when there is randomness. The transceiver 150A can improve the performance of removing the self-interference signal.

  FIG. 6 shows another embodiment of a transceiver. The same or similar elements as those described in FIG. 4 are denoted by the same or similar reference numerals, and detailed description thereof will be omitted.

  The transceiver 150B shown in FIG. 6 includes a transmission unit 10, a reception unit 40, a local oscillator 50, a clock generator 60, a time variation component extraction unit 70, a control unit 80b, a replica generation circuit 100, a cancellation unit 110, and residual component removal. Part 120.

  The control unit 80b is a processor or the like, and controls each element of the transceiver 150B by executing a program stored in a storage device such as a memory included in the transceiver 150B. The control unit 80b operates as a replica generation unit 81b and a determination unit 82 by executing a program.

  The replica generation unit 81b receives a digital transmission signal including data, like the replica generation unit 81a illustrated in FIG. Further, the replica generation unit 81b generates time variation components that give time variation to the amplitude and phase of the transmission signal extracted by the time variation component extraction unit 70 (that is, the LO signal of the local oscillator 50 and the clock jitter of the clock generator 60). get. The replica generation unit 81b changes the amplitude and phase of the digital transmission signal received using the acquired time-varying component, and the replica signal of the transmission signal subjected to pseudo processing of the DAC 11 and the mixer 12 of the transmission unit 10 Is generated.

  Similarly to the replica generation unit 81a illustrated in FIG. 4, the replica generation unit 81b uses the reception signal received by the reception unit 40 to generate a wraparound self-interference signal that has been transmitted through the reception antenna 30. Detect the time of arrival. Note that, when the replica generation unit 81b detects the time when the wraparound self-interference signal arrives, it is preferable that the control unit 80b temporarily stops the operations of the replica generation circuit 100 and the cancellation unit 110. The control unit 80b preferably restarts the operations of the replica generation circuit 100 and the cancellation unit 100 after the time when the replica generation unit 81b detects the arrival of the self-interference signal.

  Similarly to the replica generation unit 81a shown in FIG. 4, the replica generation unit 81b uses the time variation components of the amplitude and phase in the received signal extracted by the time variation component extraction unit 70 at the timing of the detected time. Generate a reference signal. The replica generation unit 81b compares the generated reference signal with the wraparound self-interference signal included in the reception signal received by the reception unit 40, and compares the relative amplitude and phase between the reference signal and the wraparound self-interference signal. Is obtained. Then, the control unit 80b outputs the propagation time and the difference information obtained by the replica generation unit 81b to the replica generation circuit 100 at the timing of the detected time.

  Note that a part of the wraparound self-interference signal included in the received signal is subjected to distortion, delay, etc. in propagation, and therefore remains as a residual component without being removed by the cancel unit 110. Therefore, the replica generation unit 81b generates a replica signal of the residual component of the wraparound self-interference signal by adjusting the time, amplitude, and phase at which the wraparound self-interference signal arrives in the difference information. The replica generation unit 81b outputs the replica signal of the generated residual component of the wraparound self-interference signal to the residual component removal unit 120 at the timing when the adjusted residual component of the wraparound self interference signal arrives.

  The residual component removal unit 120 removes the residual component of the wraparound self-interference signal remaining in the reception signal received from the reception unit 40 using the replica signal of the residual component of the wraparound self-interference signal received from the replica generation unit 81b. For example, the residual component removing unit 120 synthesizes the replica component of the residual component of the wraparound self-interference signal with the reception signal received from the reception unit 40 in reverse phase, and removes the residual component of the wraparound self-interference signal included in the reception signal. To do.

  FIG. 7 shows an example of transmission / reception processing in the transceiver 150B shown in FIG. The processing illustrated in FIG. 7 is realized, for example, when the control unit 80b such as a processor included in the transceiver 150B executes a program stored in the storage device. Note that the processing illustrated in FIG. 7 may be executed by hardware provided in the transceiver 150B. In this case, the replica generation unit 81b and the determination unit 82 illustrated in FIG. 6 are realized by a circuit arranged in the transceiver 150B.

  Note that among the operations of the steps shown in FIG. 7, those showing the same or similar processing as the steps shown in FIG. 5 are denoted by the same step numbers, and detailed description thereof is omitted.

  The transceiver 150B executes the process of step S172 after executing the process of steps S100 to S170a shown in FIG.

  In step S172, the replica generation unit 81b adjusts the arrival time, amplitude, and phase of the wraparound self-interference signal in the difference information, and generates a replica signal of the residual component of the wraparound self-interference signal using the adjusted difference information. Then, the replica generation unit 81 b outputs a replica signal of the generated residual component of the wraparound self-interference signal to the residual component removal unit 120 at the time when the adjusted residual component of the wraparound self interference signal arrives.

  In step S175, the residual component removal unit 120 uses the replica signal of the residual component of the wraparound self-interference signal generated in step S172 to determine the residual component of the wraparound self-interference signal included in the received signal received from the reception unit 40. Remove.

  The transceiver 150B executes the processing of step S175, and then executes the processing of step S180 and step S190.

  As described above, in the embodiment shown in FIG. 6 and FIG. 7, the replica generation unit 81b has the time variation components of the amplitude and phase in the transmission signal and the reception signal extracted by the time variation component extraction unit 70 (ie, AGC 43, local oscillator). 50 and the clock generator 60) to generate a reference signal. The replica generation unit 81b compares the generated reference signal with the wraparound self-interference signal included in the reception signal received by the reception unit 40, and compares the relative amplitude and phase between the reference signal and the wraparound self-interference signal. Is obtained. Then, the replica generation circuit 100 uses the propagation time and the difference information received from the control unit 80b, delays the transmission signal received from the transmission unit 10 by the propagation time, changes the amplitude and phase, and generates the wraparound self-interference signal. Generate a replica signal.

  Thus, the transceiver 150B can generate a signal for removing the wraparound self-interference signal from the received signal with high accuracy even when the wraparound self-interference signal is subject to fluctuations when there is randomness in the transceiver 150B. The transceiver 150B can improve the performance of removing the self-interference signal.

  The replica generation unit 81b adjusts the arrival time, amplitude, and phase of the wraparound self-interference signal in the difference information, and generates a replica signal of the residual component of the wraparound self-interference signal using the adjusted difference information. Then, the residual component removal unit 120 removes the residual component of the wraparound self-interference signal included in the received signal received from the reception unit 40, using the generated replica signal of the residual component of the wraparound self-interference signal. Thereby, the transceiver 150B can remove the received wraparound self-interference signal from the received signal with high accuracy.

  FIG. 8 shows another embodiment of a transceiver. The same or similar elements as those described in FIG. 1 are denoted by the same or similar reference numerals, and detailed description thereof will be omitted.

  A transceiver 150C illustrated in FIG. 8 includes a transmission unit 10, a reception unit 40, a local oscillator 50, a clock generator 60, a time variation component extraction unit 70, a control unit 80c, and a cancellation unit 90.

  The control unit 80c is a processor or the like, and controls each element of the transceiver 150C by executing a program stored in a storage device such as a memory included in the transceiver 150C. The control unit 80c operates as a replica generation unit 81c and a determination unit 82 by executing a program.

  For example, the replica generation unit 81c receives a part of the transmission signal output from the transmission unit 10 as a replica signal of the transmission signal via the ADC included in the control unit 80c. That is, the replica generation unit 81c receives a part of the transmission signal output from the transmission unit 10, so that the time variation component extraction unit 70 performs the time variation component of the transmission signal (that is, the LO signal and the clock of the local oscillator 50). A replica signal of the transmission signal can be acquired without extracting the clock jitter of the generator 60. Thereby, the calculation amount of the control part 80c can be suppressed.

  Similarly to the replica generation unit 81 illustrated in FIG. 1, the replica generation unit 81 c detects the time when the self-interference signal arrives through the reception antenna 30 using the reception signal received by the reception unit 40. . Then, for example, the replica generation unit 81c obtains a propagation time from when the transmission unit 10 transmits a transmission signal until the reception unit 40 wraps around and receives the own interference signal. The propagation time is, for example, a time obtained by subtracting, from the time between the output time of the transmission unit 10 and the output time of the reception unit 40, the total of the passage time between the input and output of the reception unit 40 measured in advance according to the RF to be used. Is calculated as

  Then, similarly to the replica generation unit 81 shown in FIG. 1, the replica generation unit 81c uses the time variation components of the amplitude and phase in the reception signal extracted by the time variation component extraction unit 70 at the timing of the detected time, Generate a reference signal. The replica generation unit 81c compares the generated reference signal with the wraparound self-interference signal included in the reception signal received by the reception unit 40, and compares the relative amplitude and phase between the reference signal and the wraparound self-interference signal. Is obtained. The replica generation unit 81c changes the amplitude and phase of the reference signal using the obtained difference information, and generates a replica signal of the wraparound self-interference signal. The replica generation unit 81c outputs the generated replica signal of the wraparound self-interference signal to the cancellation unit 90.

  Note that the transmission / reception processing in the transceiver 150C shown in FIG. 8 is the same as or similar to the processing shown in FIG. 1, and detailed description thereof is omitted.

  As described above, in the embodiment shown in FIG. 8, the replica generation unit 81c generates the replica signal of the wraparound self-interference signal using the time variation component of the amplitude and phase in the received signal extracted by the time variation component extraction unit. To do. Thus, the transceiver 150C can generate a signal for removing the wraparound self-interference signal from the received signal with high accuracy even when the wraparound self-interference signal is subject to fluctuations in the transceiver 150 when there is randomness. The transceiver 150C can improve the performance of removing the self-interference signal.

  Further, the replica generation unit 81c receives a part of the transmission signal output from the transmission unit 10 as a replica signal of the transmission signal. That is, the replica generation unit 81c receives a part of the transmission signal output from the transmission unit 10, so that the time variation component extraction unit 70 does not extract the time variation component of the transmission signal, and thus the replica signal of the transmission signal. The transceiver 150C can suppress the amount of calculation.

  From the above detailed description, features and advantages of the embodiments will become apparent. This is intended to cover the features and advantages of the embodiments described above without departing from the spirit and scope of the claims. Also, any improvement and modification should be readily conceivable by those having ordinary knowledge in the art. Therefore, there is no intention to limit the scope of the inventive embodiments to those described above, and appropriate modifications and equivalents included in the scope disclosed in the embodiments can be used.

DESCRIPTION OF SYMBOLS 10 ... Transmitter; 11 ... DAC; 12, 42, 76 ... Mixer; 13 ... PA; 20 ... Transmit antenna; 30 ... Receive antenna; 40 ... Receiver; 41 ... LNA; 43 ... AGC; 73 ... ADC; 50 ... Local oscillator; 60 ... Clock generator; 70 ... Time variation component extracting unit; 74 ... Delay unit; 75 ... 90 degree phase shifter; 77 ... LPF; 80, 80a, 80b, 80c ... Control unit; 81, 81a, 81b, 81c ... replica generation unit; 82 ... determination unit; 90, 110 ... cancellation unit; 100 ... replica generation circuit; 120 ... residual component removal unit; 150, 150A, 150B, 150C ... transceiver

Claims (7)

A transceiver that performs simultaneous transmission and reception of radio waves in the same frequency band,
An extractor for extracting time-varying components of a transmission signal and a reception signal transmitted and received by the transceiver;
A first generation unit that generates a replica signal that is a replica of the transmission signal using the extracted time-varying component;
A detection unit for detecting, using the received signal, a time at which a wraparound self-interference signal arrived by the transmission signal of the device itself included in the received signal;
A second generation unit that generates a reference signal using the replica signal of the transmission signal, the extracted time-varying component, and the detected time;
The reference signal is compared with the wraparound self-interference signal, difference information indicating a difference in amplitude and phase between the reference signal and the wraparound self-interference signal is obtained, and the reference signal is obtained using the obtained difference information. A third generation unit that generates a replica signal that is a replica of the wraparound self-interference signal,
A cancellation unit that removes the wraparound self-interference signal from the received signal using a replica signal of the wraparound self-interference signal;
The residual component of the wraparound self-interference signal remaining in the received signal from which the wraparound self-interference signal has been removed is compared with a threshold value, and the wraparound self-interference signal is removed from the reception signal output from the cancel unit. A transceiver for determining whether or not.   The extraction unit includes a first local oscillation signal used for frequency conversion or modulation of the transmission signal or a phase noise of the first local oscillation signal and a first clock signal used for digital-analog conversion of the transmission signal or Used for clock jitter of the first clock signal, phase noise of the second local oscillation signal or the second local oscillation signal used for frequency conversion or demodulation of the reception signal, and analog-digital conversion of the reception signal. 2. The transceiver according to claim 1, wherein one or more of the time-varying components of the second clock signal or the clock jitter of the second clock signal are extracted. An automatic gain controller that automatically adjusts the gain for the received signal;
The transceiver according to claim 1 or 2, wherein the extraction unit extracts gain information of a gain controlled by the automatic gain control unit as the time-varying component. A transceiver that performs simultaneous transmission and reception of radio waves in the same frequency band,
An extractor for extracting time-varying components of a transmission signal and a reception signal transmitted and received by the transceiver;
A first generation unit that generates a replica signal that is a replica of the transmission signal using the extracted time-varying component;
A detection unit for detecting, using the received signal, a time at which a wraparound self-interference signal arrived by the transmission signal of the device itself included in the received signal;
A second generation unit that generates a reference signal using the replica signal of the transmission signal, the extracted time-varying component, and the detected time;
A comparison unit that compares the reference signal with the wraparound self-interference signal and obtains difference information indicating a difference in amplitude and phase between the reference signal and the wraparound self-interference signal;
A third generation unit that generates a replica signal that is a replica of the wraparound self-interference signal from the transmission signal using the difference information;
A cancellation unit that removes the wraparound self-interference signal from the received signal using a replica signal of the wraparound self-interference signal;
The residual component of the wraparound self-interference signal remaining in the received signal from which the wraparound self-interference signal has been removed is compared with a threshold value, and the wraparound self-interference signal is removed from the reception signal output from the cancel unit. A transceiver for determining whether or not. A transceiver that performs simultaneous transmission and reception of radio waves in the same frequency band,
An extraction unit for extracting a time-varying component of a received signal received by the transceiver;
A first generation unit that generates a replica signal that is a replica of a transmission signal using the extracted time-varying component;
A detection unit for detecting, using the received signal, a time at which a wraparound self-interference signal arrived by the transmission signal of the device itself included in the received signal;
A second generation unit that generates a reference signal using the replica signal of the transmission signal, the extracted time-varying component, and the detected time;
The reference signal is compared with the wraparound self-interference signal, difference information indicating a difference in amplitude and phase between the reference signal and the wraparound self-interference signal is obtained, and the reference signal is obtained using the obtained difference information. A third generation unit that generates a replica signal that is a replica of the wraparound self-interference signal,
A cancellation unit that removes the wraparound self-interference signal from the received signal using a replica signal of the wraparound self-interference signal;
The residual component of the wraparound self-interference signal remaining in the received signal from which the wraparound self-interference signal has been removed is compared with a threshold value, and the wraparound self-interference signal is removed from the reception signal output from the cancel unit. A transceiver for determining whether or not.   The extraction unit includes a local oscillation signal used for frequency conversion or demodulation of the received signal or a phase noise of the local oscillation signal, a clock signal used for analog-digital conversion of the received signal, or a clock jitter of the clock signal. The transceiver according to claim 5, wherein at least one of the time-varying components is extracted. An automatic gain controller that automatically adjusts the gain for the received signal;
The transceiver according to claim 5 or 6, wherein the extraction unit extracts gain information of a gain controlled by the automatic gain control unit as the time-varying component.

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