CN104954307B - A kind of co-channel full duplex limit self-interference cancellation system simultaneously - Google Patents
A kind of co-channel full duplex limit self-interference cancellation system simultaneously Download PDFInfo
- Publication number
- CN104954307B CN104954307B CN201510262792.4A CN201510262792A CN104954307B CN 104954307 B CN104954307 B CN 104954307B CN 201510262792 A CN201510262792 A CN 201510262792A CN 104954307 B CN104954307 B CN 104954307B
- Authority
- CN
- China
- Prior art keywords
- radio frequency
- module
- processing unit
- signal processing
- channel
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000012545 processing Methods 0.000 claims abstract description 123
- 238000012937 correction Methods 0.000 claims abstract description 39
- 230000006854 communication Effects 0.000 abstract description 14
- 238000004891 communication Methods 0.000 abstract description 14
- 238000001228 spectrum Methods 0.000 abstract description 6
- 238000000605 extraction Methods 0.000 abstract description 3
- 238000000034 method Methods 0.000 description 22
- 230000005540 biological transmission Effects 0.000 description 16
- 238000010586 diagram Methods 0.000 description 7
- 230000000694 effects Effects 0.000 description 7
- 238000011156 evaluation Methods 0.000 description 5
- 238000006243 chemical reaction Methods 0.000 description 3
- 230000008054 signal transmission Effects 0.000 description 3
- 238000003379 elimination reaction Methods 0.000 description 2
- 238000001914 filtration Methods 0.000 description 2
- 230000002452 interceptive effect Effects 0.000 description 2
- 238000007781 pre-processing Methods 0.000 description 2
- 230000001629 suppression Effects 0.000 description 2
- 238000004148 unit process Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000007175 bidirectional communication Effects 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000008030 elimination Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 238000005070 sampling Methods 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 238000007493 shaping process Methods 0.000 description 1
- 230000003595 spectral effect Effects 0.000 description 1
Landscapes
- Noise Elimination (AREA)
Abstract
The invention discloses a kind of co-channel full duplex limit self-interference cancellation system simultaneously, mainly including antenna element, baseband signal processing unit, Radio frequency interference reconstruction unit, the first radio frequency transmitting channel, the second radio frequency transmitting channel, the first RF FEEDBACK passage, the second RF FEEDBACK passage and the first radio frequency reception channel；By signal precorrection, non-linear and extraction of mutually making an uproar, Radio frequency interference is rebuild, digital interference is offset and completes self-interference signal counteracting, in transmitting terminal setting signal precorrection module and regulator module, Radio frequency interference reconstruction unit, digital interference cancellation module are set, while extract the non-linear self-interference of transmitting and the non-linear self-interference of pre-correction signal.The present invention is applied under co-channel full duplex environment simultaneously, joint transmitting terminal and receiving terminal eliminate co-channel interference simultaneously, self-interference cancellation performance is accomplished into the limit, not only make the availability of frequency spectrum double, and improve the communication quality of system, communication equipment is improved at the same time with the Stability and dependability to be worked in the environment of frequency.
Description
Technical Field
The invention relates to an interference self-elimination system in the field of wireless communication, in particular to a simultaneous same-frequency full-duplex limit self-interference cancellation system.
Background
The current wireless communication system adopts a time division duplex or frequency division duplex method to carry out bidirectional communication. The time division duplex system uses the same frequency but different time slots to transmit data, thereby isolating the interference between an uplink and a downlink. Frequency division duplex systems use the same time slot but different frequencies to transmit data, thereby isolating interference between the uplink and downlink. The two duplex methods respectively sacrifice time resources and frequency resources in the process of isolating uplink and downlink, so that the frequency spectrum utilization rate is low.
The demand of the modern society for wireless data service is increasing day by day, and the degree of crowding of the spatial wireless channel is more and more prominent, which compels people to continuously seek new methods to improve the utilization rate of frequency spectrum resources and the anti-interference performance of equipment. If the wireless communication device uses the same time, same frequency full duplex technology to transmit and receive wireless signals, it will undoubtedly double the spectral efficiency of the wireless communication link.
However, when the transmitting end and the receiving end of the wireless communication device work at the same time, the transmitting signal generated by the transmitting end enters the receiving channel of the receiving end to form self-signal interference, and the self-interference strength is far stronger than the strength of the signal from the far-end wireless communication device received by the receiving end, so that the receiving of the signal transmitted by the far-end wireless device by the receiving end is seriously affected. In general, this will reduce the sensitivity of the receiving end, increase the error rate, and cause the communication performance to be reduced; in severe cases, the receiving channel of the receiving end is blocked, which results in complete loss of receiving function and even burning of the front end of the receiver.
In order to realize simultaneous transmission of the same frequency and improve the spectrum efficiency of wireless communication, an effective interference cancellation technique is very important, and related interference cancellation methods have appeared in the prior art.
For example, chinese patent application No. 200710162086.8 discloses a co-site interference cancellation system and method. In the technical scheme disclosed in the patent, a transmission signal of a co-site interference base station is used as an interference cancellation signal, transmitted to a receiving base station for time delay, amplitude and phase adjustment, and then added with an interference signal received by a receiving antenna to complete cancellation. However, the method only considers the adjustment of the radio frequency receiving end to the self-interference signal, and does not consider the effective elimination of the interference by factors such as multipath, nonlinearity and phase noise.
Chinese patent application No. 200610113054.4 discloses an interference cancellation method suitable for co-frequency co-timeslot duplexing. In the technical scheme disclosed in the patent, interference cancellation is performed by a method of signal preprocessing and antenna arrangement in a receiver. According to the method, the signal preprocessing needs system protocol coordination, a special time slot for stopping the wireless terminal from sending signals is set, and the receiving antenna needs to be placed at the minimum point position interfering the radiation of the transmitting antenna as far as possible, so that the operation is troublesome during specific implementation.
Chinese patent application No. 201210035077.3 discloses a method for simultaneous co-frequency operation among multiple electromagnetic devices in a single carrier. In the technical scheme disclosed in the patent, a plurality of devices in a single carrier with limited area or limited volume are added with a digital interface and an analog interface, and interference cancellation is completed through analog interference suppression and digital interference suppression in the receiving flow of each device. However, this method does not consider radio frequency self-interference cancellation at the joint transmitting end, and also does not cancel the effects of non-linearity and phase noise in self-interference.
In summary, the existing self-interference cancellation technical solution does not consider how to cancel the self-interference to the limit in the presence of nonlinearity, phase noise and multipath.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provide a simultaneous same-frequency full-duplex limit self-interference cancellation system, which is combined with a sending end and a receiving end to eliminate simultaneous same-frequency self-interference, eliminate non-linearity and phase noise, improve the frequency spectrum utilization rate and improve the self-interference cancellation performance to the utmost extent, so that communication equipment can work more stably in the environment with the same frequency at the same time.
The purpose of the invention is realized by the following technical scheme: a simultaneous co-frequency full-duplex limit self-interference cancellation system comprises an antenna unit, a baseband signal processing unit, a radio frequency interference reconstruction unit, a first radio frequency transmitting channel, a second radio frequency transmitting channel, a first radio frequency feedback channel, a second radio frequency feedback channel and a first radio frequency receiving channel.
The first transmitting end of the baseband signal processing unit is connected with the transmitting end of the antenna unit, the input end of the radio frequency interference reconstruction unit and the input end of the first radio frequency feedback channel through the first radio frequency transmitting channel, the output end of the first radio frequency feedback channel is connected with the first feedback end of the baseband signal processing unit, the output end of the radio frequency interference reconstruction unit and the receiving end of the antenna unit are connected with the input end of the first radio frequency receiving channel through the first adder, and the output end of the first radio frequency receiving channel is connected with the receiving end of the baseband signal processing unit.
The second sending end of the baseband signal processing unit is connected with the input end of a second radio frequency transmitting channel, the output end of the second radio frequency transmitting channel is connected with the input end of a second radio frequency feedback channel, the second radio frequency transmitting channel is further connected with the input end of a first radio frequency receiving channel through a first adder, and the output end of the second radio frequency feedback channel is connected with the second feedback end of the baseband signal processing unit.
The antenna unit comprises a transmitting and receiving antenna 3, the transmitting end and the receiving end of the antenna unit share the transmitting and receiving antenna 3, and the transmitting and receiving antenna 3 is respectively connected with the transmitting end and the receiving end of the antenna unit through a circulator 4.
The antenna unit comprises a plurality of antennas, a transmitting end antenna 1 and a receiving end antenna 2 are respectively arranged at a transmitting end and a receiving end of the antenna unit, the transmitting end antenna 1 is connected with the transmitting end of the antenna unit, and the receiving end antenna 2 is connected with the receiving end of the antenna unit.
The baseband signal processing unit comprises a baseband transmitting signal processing unit, a baseband receiving signal processing unit, a channel estimation module, a signal pre-correction module, a digital interference cancellation module, a first adjuster module and a second adjuster module.
The output end of the baseband emission signal processing unit is respectively connected with the first transmitting end of the baseband signal processing unit, the first adjuster module, the channel estimation module, the signal pre-correction module and the input end of the digital interference cancellation module, and the baseband emission signal processing unit is also connected with the baseband receiving signal processing unit.
The input end of the baseband receiving signal processing unit is connected with the output end of the digital interference cancellation module, and the input end of the digital interference cancellation module is respectively connected with the receiving end of the baseband signal processing unit, the first feedback end of the baseband signal processing unit, the second feedback end of the baseband signal processing unit and the output end of the signal pre-correction module.
The input end of the first adjuster module is further connected with the first feedback end of the baseband signal processing unit, and the output end of the first adjuster module and the output end of the first radio frequency feedback channel are connected with the first feedback end of the baseband signal processing unit through the second adder.
The input end of the second modulator module is respectively connected with the output end of the signal pre-correction module and the second feedback end of the baseband signal processing unit, and the output end of the second modulator module and the output end of the second radio frequency feedback channel are connected with the first feedback end of the baseband signal processing unit through a third adder.
The input end of the channel estimation module is further connected with the receiving end of the baseband signal processing unit, the output end of the channel estimation module is connected with the input end of the signal pre-correction module, and the output end of the signal pre-correction module is further connected with the second sending end of the baseband signal processing unit.
The digital interference cancellation module comprises a nonlinear and phase noise interference reconstruction module, a linear digital interference reconstruction module and a fourth adder.
The input end of the fourth adder is respectively connected with the output end of the nonlinear and phase noise interference reconstruction module, the output end of the linear digital interference reconstruction module and the receiving end of the baseband signal processing unit, and the output end of the fourth adder is respectively connected with the input end of the baseband received signal processing unit, the input end of the nonlinear and phase noise interference reconstruction module and the input end of the linear digital interference reconstruction module.
The input end of the nonlinear and phase noise interference reconstruction module is further connected with the output end of the signal pre-correction module, the output end of the baseband emission signal processing unit, the first feedback end of the baseband signal processing unit, the second feedback end of the baseband signal processing unit and the receiving end of the baseband signal processing unit respectively.
The input end of the linear digital interference reconstruction module is also respectively connected with the output end of the signal pre-correction module, the output end of the baseband emission signal processing unit and the receiving end of the baseband signal processing unit.
The output end of the first adder is also connected with the input end of the radio frequency interference reconstruction unit.
The radio frequency interference reconstruction unit comprises a time delay adjusting module, an amplitude modulation module, a phase modulation module and a control module, wherein the control module is respectively connected with control ends of the time delay adjusting module, the amplitude modulation module and the phase modulation module which are sequentially connected in series, the input end of the time delay adjusting module is connected with the input end of the radio frequency interference reconstruction unit, and the output end of the phase modulation module is connected with the output end of the radio frequency interference reconstruction unit.
And a first amplifier and a third analog-to-digital converter ADC III which are connected in series are further arranged between the second adder and the first feedback end of the baseband signal processing unit, and a second digital-to-analog converter DAC II is further arranged between the second adder and the output end of the first regulator module.
And a second amplifier and a first analog-to-digital converter ADC I are also arranged between the third adder and the second feedback end of the baseband signal processing unit. And a fourth digital-to-analog converter DAC IV is also arranged between the third adder and the output end of the second regulator module.
And a first digital-to-analog converter DAC I is arranged between the input end of the first radio frequency transmitting channel and the first transmitting end of the baseband signal processing unit.
And a third digital-to-analog converter DAC III is arranged between the input end of the second radio frequency transmitting channel and the second transmitting end of the baseband signal processing unit.
And a second analog-to-digital converter ADC II is arranged between the output end of the first radio frequency receiving channel and the receiving end of the baseband signal processing unit.
The system provided by the invention is based on a simultaneous same-frequency full-duplex limit self-interference cancellation method, and the method comprises a signal transmission step, wherein the signal transmission step comprises the following substeps:
s101: the baseband emission signal processing unit processes a plurality of paths of signals to be transmitted to obtain a plurality of paths of digital signals B ═ B1,b2,...,bM) Wherein b is1,b2,...,bMRespectively representing the 1 st, 2 nd and up to Mth sending data sent by the sending end of the antenna unit, wherein M is the number of sending antennas;
s102: the multi-channel digital signal B is respectively sent to a first digital-to-analog converter, a first regulator module, a channel estimation module, a signal pre-correction module and a digital interference cancellation module;
s103: after the multi-channel digital signal B sent into the first digital-to-analog converter is subjected to digital-to-analog conversion, the multi-channel digital signal B is sent to the first radio frequency transmitting channel, and one or more channels of radio frequency signals S (S) to be sent at the sending end of the antenna unit are obtained1,s2,...,sM) Wherein s is1,s2,...,sMRespectively representing the data to be sent from the 1 st, the 2 nd to the Mth at the sending end of the antenna unit, and one or more paths of radio frequency signals S are also transmitted to a radio frequency interference reconstruction unit;
s104: the signal obtained by adjusting the multi-path digital signal B by the first adjuster module is processed by the second digital-to-analog converter to form a cancellation signalWherein,respectively represent the 1 st, the 2 nd to the Mth counteracting signals;
s105: according to the self-interference signal R ═ (R) received by the receiving end of the antenna unit1,r2,...,rL) Obtaining signals after radio frequency self-interference cancellationThe signal passes through a first radio frequency receiving channel and a second analog-to-digital converter in sequenceAfter conversion, the digital signal after radio frequency offset is obtainedAnd fed into a channel estimation module, where r1,r2,...,rLRespectively representing the 1 st, 2 nd and L th received data received by the receiving end of the antenna unit,respectively represent signals after 1 st, 2 nd to Lth radio frequency self-interference cancellation,respectively representing the digital signals after the 1 st, the 2 nd and the L-th radio frequency cancellation, wherein L is the number of receiving antennas;
s106: the channel estimation module cancels the digital signal R according to the digital signal B to be transmitted and the radio frequencybAcquiring the multipath wireless channel characteristics between the transmitting terminal and the receiving terminal by means of channel estimation
S107: the signal pre-correction module is based on the channel characteristicsCarrying out distortion processing on a digital signal B to be transmitted to obtain a pre-corrected digital signal A ═ a1,a2,...,aL) Wherein a is1,a2,...,aLRespectively representing the 1 st, the 2 nd to the Lth pre-corrected digital signals;
s108: the pre-corrected digital signal A is sent to a second regulator module, and simultaneously the digital signal A also sequentially passes through a third digital-to-analog converter and a second radio frequency transmission channel to output a pre-corrected radio frequency signalWherein,respectively representing the 1 st, the 2 nd to the Lth pre-corrected radio frequency signals;
s109: the second regulator module regulates the pre-corrected digital signal A to form a counteracting signal through a fourth digital-to-analog converterWherein,respectively represent the 1 st, 2 nd, through lth cancellation signals.
The self-interference cancellation method further comprises a signal receiving step, the signal receiving step comprising the following sub-steps:
s201: the receiving end of the antenna unit receives the self-interference signal R ═ (R) of the transmitting end1,r2,...,rL)；
S202: the radio frequency interference reconstruction unit adjusts one or more paths of radio frequency signals S input by the antenna unit sending end and outputs adjusted radio frequency interference reconstruction signalsWherein,respectively representing the 1 st, the 2 nd and the L th adjusted radio frequency interference reconstruction signals;
s203: reconstruction of signal S from radio frequency interferenceIPrecorrected radio frequency signal ArSending the signal and a self-interference signal R received by the receiving end of the antenna unit into a first adder together for radio frequency self-interference cancellation to obtain a signal after the radio frequency self-interference cancellation
S204: the radio frequency interference reconstruction unit reconstructs the signal R according to the signalcEvaluating the radio frequency interference cancellation performance, obtaining an adjustment value aiming at one or more radio frequency signals S according to the evaluation result, entering the step S202, and repeatedly executing until the cancellation effect reaches the best, thereby completing the radio frequency interference cancellation;
s205: one or more radio frequency signals S are sent to a first radio frequency feedback channel to obtain an output signal Sb＝(sb1,sb2,...,sbM) Wherein s isb1,sb2,...,sbMRespectively represent the 1 st, the 2 nd to the Mth output signals;
s206: signal S output by first RF feedback channelb＝(sb1,sb2,...,sbM) And the offset signal formed by the first regulator module after passing through the second digital-to-analog converterTogether fed into a second adder to output a signal SbThe middle linear component is counteracted, and then the counteracted signal S is obtained by the first amplifierc＝(sc1,sc2,...,scM) Wherein s isc1,sc2,...,scMRespectively representing the signals of the 1 st, the 2 nd to the Mth after cancellation;
s207: the first regulator module is based on the signal ScEvaluating the counteracting performance, obtaining an adjusting value aiming at the multi-channel digital signal B according to the evaluating result, and obtaining a counteracting signal after adjusting the multi-channel digital signal BStep S206 is entered, the execution is repeated until the cancellation effect is optimal, and the output signal S is finishedbCancellation of the mid-linear component;
s208: precorrected radio frequency signal ArSending the signal into a second radio frequency feedback channel to obtain an output signal Ab＝(ab1,ab2,...,abL) Wherein a isb1,ab2,...,abLRespectively represent the 1 st, 2 nd to L th output signals;
s209: signal A output by the second RF feedback channelb＝(ab1,ab2,...,abL) And the offset signal formed by the second regulator module through the fourth digital-to-analog converterTogether fed into a third adder to output signal AbThe middle linear component is counteracted, and then the counteracted signal A is obtained through a second amplifier and a first analog-to-digital converterc＝(ac1,ac2,...,acL) Wherein a isc1,ac2,...,acLRespectively representing the signals of the 1 st, the 2 nd and the L th after cancellation;
s210: the second regulator module is based on the signal AcEvaluating the cancellation performance, obtaining an adjustment value aiming at the digital signal A according to the evaluation result, and obtaining a cancellation signal after adjusting the digital signal AProceeding to step S209, repeating the steps until the cancellation effect is optimal, and completing the signal AbCancellation of the mid-linear component;
s211: digital signal B to be transmitted, pre-corrected digital signal A and cancelled digital signal RbThe signal S after the cancellationcAnd the cancelled signal AcSending the signals into a digital interference counteracting unit;
s212: the digital interference cancellation unit cancels the digital signal R after the radio frequencybCarrying out digital interference cancellation to obtain a signal after digital interference cancellationDigital interference cancellation is accomplished in which, among other things,respectively represent the signals after the 1 st, 2 nd and up to the L-th digital interference cancellation.
And the working frequency bands of the transmitting end and the receiving end of the antenna unit are completely or partially overlapped.
The one or more rf signals S in step S103 are further transmitted to the rf interference reconstruction unit, which means that the one or more rf signals S are respectively coupled to one path and then transmitted to the rf interference reconstruction unit.
The adjustment in step S202 includes time delay adjustment, amplitude adjustment, and phase adjustment, and the radio frequency interference reconstruction unit adjusts the input one or more paths of radio frequency signals S by subdividing each of the input one or more paths of radio frequency signals into L paths, and then performs individual time delay adjustment, amplitude adjustment, and phase adjustment on each of the branched signals.
The channel estimation method in step S106 includes non-blind estimation and blind estimation, where the non-blind estimation is channel estimation that uses a known signal to obtain an instantaneous characteristic or a statistical characteristic of a wireless channel in combination with a signal received by a receiving end, and the blind estimation is channel estimation that uses a received signal of the receiving end to obtain a statistical characteristic of the wireless channel.
The digital interference cancellation in step S212 includes linear digital interference reconstruction and cancellation, nonlinear interference reconstruction and phase noise interference cancellation.
The reconstruction and cancellation of the linear digital interference aims at the reconstruction and cancellation of interference of a linear part of a self-interference signal, and specifically comprises the following substeps:
① the digital interference cancellation module utilizes the transmitted digital signal B and the pre-corrected digital signal A to cancel the radio frequency self-interference cancelled digital signal RbPerforming channel estimation and outputting a channel characteristic value;
②, the linear digital interference reconstruction module is used to reconstruct the linear digital interference of the digital signal B to be transmitted according to the channel characteristic value to obtain the linear digital interferenceInterfering the reconstructed signalWherein,respectively representing signals reconstructed by the 1 st, the 2 nd and the L th linear digital interference;
③ digital signal R after cancellation by radio frequency self-interferencebSubtracting the reconstructed signal of linear digital interferenceThereby completing digital interference cancellation from the linear part of the interference signal.
The reconstruction and cancellation of the nonlinear interference and the phase noise interference are carried out according to the cancelled signal ScThe signal A after the cancellationcDigital signal B to be transmitted, pre-corrected digital signal A and digital signal R after cancellationbReconstructing and canceling nonlinear interference and phase noise interference, specifically comprising the following substeps:
① according to the cancelled signal ScAnd the cancelled signal AcTo the digital signal RbThe nonlinear and phase noise characteristics introduced by the system contained in (1) are estimated;
② combining the signal S based on the non-linear and phase noise characteristic estimatescSignal AcSignal B and signal A versus digital signal RbThe nonlinear interference and the phase noise interference contained in the signal are reconstructed to obtain a signal after nonlinear digital interference reconstructionInterfering the reconstructed signal with phase noiseWherein,respectively represent signals after 1 st, 2 nd to Lth nonlinear digital interference reconstruction,respectively representing the signals after the 1 st phase noise interference reconstruction, the 2 nd phase noise interference reconstruction and the L th phase noise interference reconstruction;
③ digital signal R after cancellation by radio frequency self-interferencebSignal reconstructed by subtracting nonlinear interference and phase noise interferenceSum signalThereby completing digital interference cancellation from the non-linearity of the interference signal and the phase noise component.
The invention has the beneficial effects that: the method comprises the steps of setting a signal pre-correction module and an adjuster module at a sending end, setting a radio frequency interference reconstruction unit and a digital interference cancellation module, simultaneously extracting transmitted nonlinear self-interference and nonlinear self-interference of a pre-correction signal, eliminating simultaneous same-frequency interference by combining the sending end and a receiving end under a simultaneous same-frequency full-duplex environment, and limiting self-interference cancellation performance, so that the frequency spectrum utilization rate is doubled, the communication quality of a system is improved, and the working stability of communication equipment under the simultaneous same-frequency environment is improved.
Drawings
FIG. 1 is a block diagram of a self-interference cancellation system according to the present invention;
FIG. 2 is a block diagram of an RF interference reconstruction unit according to the present invention;
fig. 3 is a block diagram of a digital interference cancellation module according to the present invention;
fig. 4 is a block diagram of an implementation of single-transmitting and single-receiving of an antenna unit in the present invention;
fig. 5 is a block diagram of another implementation of single-transmitting and single-receiving of the antenna unit in the present invention;
in the figure, 1-transmitting terminal antenna, 2-receiving terminal antenna, 3-transceiving antenna, 4-circulator.
Detailed Description
The technical solutions of the present invention are further described in detail below with reference to the drawings and the embodiments, but the scope of the present invention is not limited to the following descriptions.
One-time same-frequency full-duplex limit self-interference cancellation system
As shown in fig. 1, a simultaneous co-frequency full-duplex limit self-interference cancellation system includes an antenna unit, a baseband signal processing unit, a radio frequency interference reconstruction unit, a first radio frequency transmission channel, a second radio frequency transmission channel, a first radio frequency feedback channel, a second radio frequency feedback channel, and a first radio frequency reception channel.
The first transmitting end of the baseband signal processing unit is connected with the transmitting end of the antenna unit, the input end of the radio frequency interference reconstruction unit and the input end of the first radio frequency feedback channel through the first radio frequency transmitting channel, the output end of the first radio frequency feedback channel is connected with the first feedback end of the baseband signal processing unit, the output end of the radio frequency interference reconstruction unit and the receiving end of the antenna unit are connected with the input end of the first radio frequency receiving channel through the first adder, and the output end of the first radio frequency receiving channel is connected with the receiving end of the baseband signal processing unit.
The second sending end of the baseband signal processing unit is connected with the input end of a second radio frequency transmitting channel, the output end of the second radio frequency transmitting channel is connected with the input end of a second radio frequency feedback channel, the second radio frequency transmitting channel is further connected with the input end of a first radio frequency receiving channel through a first adder, and the output end of the second radio frequency feedback channel is connected with the second feedback end of the baseband signal processing unit.
As shown in fig. 5, the antenna unit includes a transceiving antenna 3, the transmitting end and the receiving end of the antenna unit share the transceiving antenna 3, and the transceiving antenna 3 is connected to the transmitting end and the receiving end of the antenna unit through a circulator 4.
As shown in fig. 4, the antenna unit includes a plurality of antennas, a transmitting end antenna 1 and a receiving end antenna 2 are respectively disposed at a transmitting end and a receiving end of the antenna unit, the transmitting end antenna 1 is connected to the transmitting end of the antenna unit, and the receiving end antenna 2 is connected to the receiving end of the antenna unit.
As shown in fig. 1, the baseband signal processing unit includes a baseband transmit signal processing unit, a baseband receive signal processing unit, a channel estimation module, a signal pre-correction module, a digital interference cancellation module, a first adjuster module, and a second adjuster module.
The output end of the baseband emission signal processing unit is respectively connected with the first transmitting end of the baseband signal processing unit, the first adjuster module, the channel estimation module, the signal pre-correction module and the input end of the digital interference cancellation module, and the baseband emission signal processing unit is also connected with the baseband receiving signal processing unit.
The input end of the baseband receiving signal processing unit is connected with the output end of the digital interference cancellation module, and the input end of the digital interference cancellation module is respectively connected with the receiving end of the baseband signal processing unit, the first feedback end of the baseband signal processing unit, the second feedback end of the baseband signal processing unit and the output end of the signal pre-correction module.
The input end of the first adjuster module is further connected with the first feedback end of the baseband signal processing unit, and the output end of the first adjuster module and the output end of the first radio frequency feedback channel are connected with the first feedback end of the baseband signal processing unit through the second adder.
The input end of the second modulator module is respectively connected with the output end of the signal pre-correction module and the second feedback end of the baseband signal processing unit, and the output end of the second modulator module and the output end of the second radio frequency feedback channel are connected with the first feedback end of the baseband signal processing unit through a third adder.
The input end of the channel estimation module is further connected with the receiving end of the baseband signal processing unit, the output end of the channel estimation module is connected with the input end of the signal pre-correction module, and the output end of the signal pre-correction module is further connected with the second sending end of the baseband signal processing unit.
As shown in fig. 3, the digital interference cancellation module includes a nonlinear and phase noise interference reconstruction module, a linear digital interference reconstruction module, and a fourth adder.
The input end of the fourth adder is respectively connected with the output end of the nonlinear and phase noise interference reconstruction module, the output end of the linear digital interference reconstruction module and the receiving end of the baseband signal processing unit, and the output end of the fourth adder is respectively connected with the input end of the baseband received signal processing unit, the input end of the nonlinear and phase noise interference reconstruction module and the input end of the linear digital interference reconstruction module.
The input end of the nonlinear and phase noise interference reconstruction module is further connected with the output end of the signal pre-correction module, the output end of the baseband emission signal processing unit, the first feedback end of the baseband signal processing unit, the second feedback end of the baseband signal processing unit and the receiving end of the baseband signal processing unit respectively.
The input end of the linear digital interference reconstruction module is also respectively connected with the output end of the signal pre-correction module, the output end of the baseband emission signal processing unit and the receiving end of the baseband signal processing unit.
The output end of the first adder is also connected with the input end of the radio frequency interference reconstruction unit.
As shown in fig. 2, the radio frequency interference reconstruction unit includes a delay adjustment module, an amplitude modulation module, a phase modulation module and a control module, the control module is respectively connected to control terminals of the delay adjustment module, the amplitude modulation module and the phase modulation module which are sequentially connected in series, an input terminal of the delay adjustment module is connected to an input terminal of the radio frequency interference reconstruction unit, and an output terminal of the phase modulation module is connected to an output terminal of the radio frequency interference reconstruction unit.
As shown in fig. 1, a first amplifier and a third analog-to-digital converter ADC iii connected in series are further disposed between the second adder and the first feedback end of the baseband signal processing unit, and a second digital-to-analog converter DAC ii is further disposed between the second adder and the output end of the first regulator module.
As shown in fig. 1, a second amplifier and a first analog-to-digital converter ADC i are further disposed between the third adder and the second feedback end of the baseband signal processing unit. And a fourth digital-to-analog converter DAC IV is also arranged between the third adder and the output end of the second regulator module.
As shown in fig. 1, a first digital-to-analog converter DAC i is disposed between the input end of the first radio frequency transmission channel and the first transmitting end of the baseband signal processing unit.
As shown in fig. 1, a third digital-to-analog converter DAC iii is disposed between the input end of the second rf transmission channel and the second transmitting end of the baseband signal processing unit.
As shown in fig. 1, a second analog-to-digital converter ADC ii is disposed between the output end of the first rf receiving channel and the receiving end of the baseband signal processing unit.
In the simultaneous co-frequency full-duplex limit self-interference cancellation system, at a transmitting end, a baseband sending signal processing module sends a digital signal to be sent to a first regulator module I, a signal pre-correction module and a digital interference cancellation module, and a radio-frequency signal to be sent is sent to a radio-frequency interference reconstruction unit and a first radio-frequency feedback channel I. The signal output by the first adjuster module I passes through the second digital-to-analog converter II to form a counteracting signal of the first radio frequency feedback channel I. The signal output by the signal pre-correction module forms a pre-corrected radio frequency signal through a digital-to-analog converter III and a radio frequency transmission channel II. And the pre-corrected radio frequency signal is sent to a radio frequency feedback channel II. And the signal output by the signal pre-correction module forms a counteracting signal of a radio frequency feedback channel II through a regulator module II and a digital-to-analog converter IV.
At a receiving end, the self-interference signal received by the antenna subtracts the pre-corrected radio frequency signal and the radio frequency signal processed by the radio frequency interference reconstruction unit to complete radio frequency self-interference cancellation, the cancelled signal is sent to the digital interference cancellation module, and digital interference cancellation is completed by combining the digital signal to be sent, the cancellation signal of the adjuster module I and the radio frequency feedback channel I, the cancellation signal of the adjuster module II and the radio frequency feedback channel II and the pre-corrected digital signal.
In the invention, the sending end and the receiving end work simultaneously, and the communication frequency points are f0。
And the baseband transmitting signal processing unit is used for generating a digital signal to be transmitted.
And the channel estimation module is used for acquiring the characteristics of the self-interference channel.
And the signal pre-correction module is used for pre-correcting the digital signal to be transmitted according to the self-interference channel characteristic.
DAC I, DAC II, DAC III and DAC IV which are used for converting digital signals into analog signals.
ADC I, ADC II and ADC III are used for converting the analog signals into the digital signals.
And the radio frequency transmission channel I and the radio frequency transmission channel II are used for radio frequency transmission processing.
And the radio frequency receiving channel I, the radio frequency feedback channel I and the radio frequency feedback channel II are used for radio frequency receiving processing.
And the antenna unit is used for transmitting and receiving wireless signals.
And the radio frequency interference reconstruction unit is used for reconstructing the radio frequency self-interference signal.
And the regulator module I is used for generating a cancellation signal of the output signal of the radio frequency feedback channel I.
And the regulator module II is used for generating a cancellation signal of the output signal of the radio frequency feedback channel II.
And the adder I is used for canceling the radio frequency self-interference signal.
And the adder II is used for offsetting the output signal of the regulator module I and the output signal of the radio frequency feedback channel I.
And the adder III is used for offsetting the output signal of the regulator module II and the output signal of the radio frequency feedback channel II.
And the digital interference cancellation module is used for reconstructing digital self-interference and canceling the digital self-interference.
And the baseband receiving signal processing unit is used for carrying out other receiving processing on the signal after the self-interference cancellation.
The system provided by the invention is based on a simultaneous same-frequency full-duplex limit self-interference cancellation method, which comprises a signal transmitting step and a signal receiving step, wherein a transmitting end transmits N data symbols in total under the assumption of BPSK modulation, the number of antennas at the transmitting end is M-1, and the number of antennas at a receiving end is L-1.
The signal transmission comprises the following steps:
s101: and the baseband emission signal processing unit processes the signal to be transmitted to obtain a digital signal b (i).
S102: the digital signals b (i) are respectively sent to a digital-to-analog converter I (DAC I), a channel estimation module, a signal pre-correction module, a regulator module I and a digital interference cancellation module.
S103: after digital-to-analog conversion is performed on a digital signal b (i) sent into a digital-to-analog converter I (DAC I), the digital signal b (i) is sent to a radio frequency transmitting channel I, a radio frequency signal s (t) to be sent at a sending end of an antenna unit is obtained, the radio frequency signal s (t) is also sent to a radio frequency interference reconstruction unit, and the radio frequency signal s (t) is represented as:
wherein,representing a real part; eSIs the transmit power; t isSIs one data symbol period; g (t) is a baseband shaping pulse; f. of0Representing a radio frequency point; b (i) is the signal transmitted by the transmit antenna for the ith symbol duration.
S104: the regulator module I adjusts the amplitude, phase and time delay of the digital signals b (i), and the adjusted signals form offset signals through a digital-to-analog converter IIWherein,is an amplitude adjustment value,Is a phase adjustment value,Is a delay adjustment value.
S105: obtaining a signal r after radio frequency self-interference cancellation according to a self-interference signal r (t) received by a receiving end of an antenna unitc(t), the signal is converted by a radio frequency receiving channel I and an analog-to-digital converter II in sequence to obtain a digital signal r after radio frequency cancellationb(i) And sent to the channel estimation module.
S106: the channel estimation module is used for estimating the channel according to the digital signal b (i) to be transmitted and the digital signal r after radio frequency cancellationb(i) Acquiring the multipath channel characteristics between the transmitting end and the receiving end by a channel estimation methodIn a multipath channel, the channel characteristics can be expressed by:
where p (t) is the total channel characteristics sent to receive; q (t) is the primary path channel characteristics sent to the receiver,h (t) are other multipath channel characteristics sent to the receiver,Npath+1 is the number of multipaths sent to reception αlAttenuation for the l-th path between transmission and reception; thetalPhase offset for the ith path from send to receive; tau islIs the delay of the ith path between transmission and reception.
The channel estimation method comprises non-blind estimation and blind estimation, wherein the non-blind estimation is to use known signals, namely digital signals b (i) to be sent into a channel estimation module I, to combine signals received by a receiving end to obtain channel estimation of instantaneous characteristics or statistical characteristics of a wireless channel, and the blind estimation is to use the received signals of the receiving end to obtain channel estimation of the statistical characteristics of the wireless channel. The radio channel characteristics may be time domain characteristics of the radio channel or frequency domain characteristics of the radio channel.
S107: the signal pre-correction module is based on the channel characteristicsCarrying out distortion processing on a digital signal b (i) to be transmitted to obtain a pre-corrected digital signal a (i):
wherein denotes a convolution;g is a constant; h (i) is a sample of h (T), h (i) ═ h (it), and T is a sampling period.
The distortion processing of the signal may be time-domain filtering processing or frequency-domain filtering processing. The signal pre-correction module will output a corrected signal.
S108: the pre-corrected digital signals a (i) are sent to a regulator module II, and simultaneously the digital signals a (i) also sequentially pass through a digital-to-analog converter III (DAC III) and a radio frequency emission channel II to output pre-corrected radio frequency signals
S109: the adjuster module II adjusts the amplitude, phase and time delay of the pre-corrected digital signals a (i), and the adjusted signals form offset signals through a digital-to-analog converter IVWherein,is an amplitude adjustment value,Is a phase adjustment value,Is a delay adjustment value.
At this point, the transmitting step is completed.
The signal receiving comprises the following steps:
s201: the receiving end of the antenna unit receives the self-interference signal r (t) from the transmitting end, which is represented as:
r(t)＝s(t)*p(t)+w(t)；
wherein, r (t) represents the self-interference signal received by the receiving end antenna; w (t) represents the noise introduced.
S202: the radio frequency interference reconstruction unit adjusts the time delay, the amplitude and the phase of the radio frequency signal s (t) input by the sending end according to the time delay, the amplitude and the phase adjustment value output by the control module, as shown in fig. 4, outputs the adjusted radio frequency interference reconstruction signal sI(t)：
Wherein, taurIndicating the adjustment of the time delay for s (t); αrRepresents the amplitude adjustment made to s (t); thetarThe phase adjustment performed on s (t) is shown.
S203: reconstruction of a signal s by radio frequency interferenceI(t) precorrected radio frequency signal ar(t) sending the self-interference signal r (t) received by the receiving end of the antenna unit into an adder I together for radio frequency self-interference cancellation to obtain a signal r after the radio frequency self-interference cancellationc(t)：
rc(t)＝r(t)-sI(t)-ar(t)。
The reduction in the cancellation of the radio frequency self-interference is realized by a coupler or a combiner.
S204: the radio frequency interference reconstruction unit is based on rc(t) evaluating the radio frequency interference cancellation performance, obtaining an adjustment value aiming at S (t) according to the evaluation result, outputting the adjustment value through the control module, entering the step S203, and repeatedly executing until the cancellation effect reaches the best, thereby completing the radio frequency interference cancellation.
S205: sending the radio frequency transmitting signal s (t) into a radio frequency feedback channel I to obtain an output signalWherein,is the amplitude variation of s (t) after passing through the radio frequency feedback channel I,Is s (t) the phase change after the RF feedback channel I,Is s (t) time delay variation after passing through radio frequency feedback channel I, snolinear(t) is s (t) the nonlinearity, s, produced after passing through the radio frequency transmission channel Iphn(t) is s (t) phase noise generated after passing through the radio frequency transmission channel I,Characterize sbA linear portion in (t);
s206: signal s output by radio frequency feedback channel Ib(t) and a cancellation signal formed by the adjuster module I after the D/A converter IIAre sent together to the adder II for sbAnd (t) the linear components are counteracted, and then the signals after the counteraction are obtained through an amplifier I:
s207: regulator module I according to sc(t) evaluating cancellation performance, obtaining amplitude, phase and time delay adjustment values aiming at b (i) according to evaluation results, and obtaining a cancellation signal after adjusting b (i)Step S206 is entered, the execution is repeated until the cancellation effect is optimal, and the S pair is completedb(t) cancellation of linear components;
s208: precorrected radio frequency signal ar(t) sending the signal to a second radio frequency feedback channel for processing to obtain an output signalWherein,is ar(t) amplitude variation after passing through the second RF feedback path,Is ar(t) phase change after passing through a second RF feedback path,Is ar(t) time delay variation after passing through a second RF feedback channel, ar,nolinear(t) is ar(t) nonlinearity after passing through a second RF transmit channel, ar,phn(t) is ar(t) phase noise generated after passing through the second RF transmission channel,Characterize abLinear portion in (t).
S209: signal a output by radio frequency feedback channel IIb(t) and a cancellation signal formed by the adjuster module II after the D/A converter IVAre sent together to adder III, pair abAnd (t) the linear components are counteracted, and then the signals after the counteraction are obtained through an amplifier II:
s210: regulator module II according to ac(t) evaluating the cancellation performance, and obtaining the amplitude, phase and time delay adjustment values aiming at a (i) according to the evaluation resulta (i) adjusting to obtain a cancellation signalProceeding to step S209, repeating the steps until the cancellation effect is optimal, and completing the pair ab(t) cancellation of linear components;
s211: digital signal b (i) to be transmitted, pre-corrected digital signal a (i), and cancelled digital signal rb(i) The cancelled signal sc(t) and the cancelled signal ac(t) are sent to the digital interference cancellation unit together.
S208: the digital interference cancellation module is used for cancelling the digital signal rb(i) Two digital interference cancellations are performed, one is linear digital interference reconstruction and cancellation, and the other is nonlinear interference and phase noise interference reconstruction and cancellation, as shown in fig. 5. Signal r after radio frequency self-interference cancellationb(i) Can be expressed as:
rb(i)＝rlinear(i)+rnonlinear(i)+rphase(i)+w(i)；
wherein r islinear(i) Is a digital representation of the linear part of the remaining self-interference signal after cancellation of the radio frequency self-interference; r isnonlinear(i) Interference signal components caused by nonlinearity after radio frequency self-interference cancellation; r isphase(i) Interference signal components caused by phase noise after radio frequency self-interference cancellation; w (i) is noise.
The linear digital interference reconstruction and cancellation carries out interference reconstruction and cancellation on a linear part of the self-interference signal, and the digital interference cancellation module cancels the radio frequency interference to obtain a digital signal rb(i) Performing channel estimation, and obtaining the signal after linear digital interference reconstruction by a linear digital interference reconstruction moduleThe method specifically comprises the following substeps:
① the digital interference cancellation module utilizes the transmitted digital signal b (i) and the pre-corrected digital signal a (i) to estimate the channel
Digital signal r after counter-cancellation of radio frequency self-interferenceb(i) Performing channel estimation and outputting a channel characteristic value;
② the linear digital interference reconstruction module reconstructs the linear digital interference to the digital signal b (i) to be sent according to the channel characteristic value to obtain the signal after the linear digital interference reconstruction
③ digital signal r after cancellation by radio frequency self-interferenceb(i) Subtracting the reconstructed signal of linear digital interferenceThereby completing digital interference cancellation from the linear part of the interference signal.
The reconstruction and cancellation of the nonlinear interference and the phase noise interference are carried out according to the cancelled signal sc(t) the cancelled signal ac(t), digital signal b (i) to be transmitted, pre-corrected digital signal a (i) and cancelled digital signal rb(i) Reconstructing and canceling nonlinear interference and phase noise interference, specifically comprising the following substeps:
① according to the cancelled signal sc(t) and the cancelled signal ac(t) for the digital signal rb(i) The nonlinear and phase noise characteristics introduced by the system contained in (1) are estimated;
② combining the signal s according to the non-linear and phase noise characteristic estimatesc(t) signal ac(t), signal rb(i) Sum signal a (i) to digital signal rb(i) The nonlinear interference and the phase noise interference contained in the signal are reconstructed to obtain a reconstructed signalAnd
③ digital signal r after cancellation by radio frequency self-interferenceb(i) Signal reconstructed by subtracting nonlinear interference and phase noise interferenceAndthereby completing digital interference cancellation from the non-linearity of the interference signal and the phase noise component.
Digitally interfering reconstructed signalAndsending the digital signal r into an adder IV to be offset with the radio frequency self-interferenceb(i) Carrying out digital interference cancellation to finally obtain a signal r after the digital interference cancellationd(i) Expressed as:
at this point, the receiving step is completed.
In the technical scheme, self-interference signal cancellation is completed mainly through signal pre-correction, nonlinear and phase noise extraction, radio frequency interference reconstruction and digital interference cancellation. The signal pre-correction is mainly completed by a channel estimation module, a signal pre-correction module, a DAC III and a radio frequency emission channel II, the nonlinear and phase noise extraction is mainly completed by a regulator module I, a regulator module II, a radio frequency feedback channel I, a radio frequency feedback channel II, an adder II and an adder III, the radio frequency interference reconstruction is mainly completed by a radio frequency interference reconstruction unit, and the digital interference cancellation is mainly completed by a digital interference cancellation module.
As shown in fig. 4 and 5, the antenna unit includes one or more antennas, a transmitting end and a receiving end of the antenna unit share one transceiver antenna 3 or respectively set a transmitting end antenna 1 and a receiving end antenna 2, and the shared transceiver antenna 3 is implemented by a circulator 4. Fig. 4 is a block diagram of an implementation of single-transmitting and single-receiving of an antenna unit, according to fig. 4, an independent use of antennas at a transmitting end and a receiving end can be realized, and fig. 5 is another block diagram of an implementation of single-transmitting and single-receiving of an antenna unit, according to fig. 5, the transmitting end and the receiving end share a transmitting and receiving antenna 3 through a circulator 4.
The working frequency bands of the sending end and the receiving end are completely or partially overlapped, the sending end inputs M paths of radio frequency signals into the antenna unit, the antenna unit can output L paths of signals at the receiving end, and the L paths of signals or the M paths of signals all refer to one path or multiple paths of signals.
The rf signals S (t) (i.e. M channels) in step S103 are further transmitted to the rf interference reconstruction unit, where each rf signal S (t) in the M channels of signals is coupled to one channel, and then transmitted to the rf interference reconstruction unit. The operation of coupling one path may be realized by a coupler or a power divider.
The radio frequency interference reconstruction unit in step 202 adjusts the radio frequency signal s (t) input by the transmitting end by subdividing each of the M input radio frequency signals into L paths, and then performing individual delay adjustment, amplitude adjustment, and phase adjustment on each of the M × L paths. The splitting into L paths may be implemented by a coupler or a power splitter. The time delay adjustment, the amplitude adjustment and the phase adjustment are realized through an adjustment algorithm, the adjustment algorithm aims at minimizing the power of a radio frequency self-interference offset result, adjusts the time delay, the phase and the amplitude, and comprises a gradient descent algorithm.
Claims (8)
1. The utility model provides a full duplex limit self-interference of same frequency simultaneously offsets system which characterized in that: the radio frequency interference reconstruction device comprises an antenna unit, a baseband signal processing unit, a radio frequency interference reconstruction unit, a first radio frequency transmitting channel, a second radio frequency transmitting channel, a first radio frequency feedback channel, a second radio frequency feedback channel and a first radio frequency receiving channel;
a first sending end of the baseband signal processing unit is respectively connected with a sending end of the antenna unit, an input end of the radio frequency interference reconstruction unit and an input end of a first radio frequency feedback channel through a first radio frequency sending channel, an output end of the first radio frequency feedback channel is connected with a first feedback end of the baseband signal processing unit, an output end of the radio frequency interference reconstruction unit and a receiving end of the antenna unit are both connected with an input end of a first radio frequency receiving channel through a first adder, and an output end of the first radio frequency receiving channel is connected with a receiving end of the baseband signal processing unit;
a second sending end of the baseband signal processing unit is connected with an input end of a second radio frequency transmitting channel, an output end of the second radio frequency transmitting channel is connected with an input end of a second radio frequency feedback channel, and is also connected with an input end of a first radio frequency receiving channel through a first adder, and an output end of the second radio frequency feedback channel is connected with a second feedback end of the baseband signal processing unit;
the baseband signal processing unit comprises a baseband transmitting signal processing unit, a baseband receiving signal processing unit, a channel estimation module, a signal pre-correction module, a digital interference cancellation module, a first adjuster module and a second adjuster module;
the output end of the baseband emission signal processing unit is respectively connected with the input ends of the first sending end, the first adjuster module, the channel estimation module, the signal pre-correction module and the digital interference cancellation module of the baseband signal processing unit, and the baseband emission signal processing unit is also connected with the baseband receiving signal processing unit;
the input end of the baseband receiving signal processing unit is connected with the output end of the digital interference cancellation module, and the input end of the digital interference cancellation module is respectively connected with the receiving end of the baseband signal processing unit, the first feedback end of the baseband signal processing unit, the second feedback end of the baseband signal processing unit and the output end of the signal pre-correction module;
the input end of the first adjuster module is also connected with the first feedback end of the baseband signal processing unit, and the output end of the first adjuster module and the output end of the first radio frequency feedback channel are connected with the first feedback end of the baseband signal processing unit through a second adder;
the input end of the second modulator module is respectively connected with the output end of the signal pre-correction module and the second feedback end of the baseband signal processing unit, and the output end of the second modulator module and the output end of the second radio frequency feedback channel are connected with the first feedback end of the baseband signal processing unit through a third adder;
the input end of the channel estimation module is further connected with the receiving end of the baseband signal processing unit, the output end of the channel estimation module is connected with the input end of the signal pre-correction module, and the output end of the signal pre-correction module is further connected with the second sending end of the baseband signal processing unit.
2. The system of claim 1, wherein the system further comprises: the antenna unit comprises a transmitting and receiving antenna (3), the transmitting end and the receiving end of the antenna unit share the transmitting and receiving antenna (3), and the transmitting and receiving antenna (3) is respectively connected with the transmitting end and the receiving end of the antenna unit through a circulator (4).
3. The system of claim 1, wherein the system further comprises: the antenna unit comprises a plurality of antennas, a transmitting end antenna (1) and a receiving end antenna (2) are respectively arranged at a transmitting end and a receiving end of the antenna unit, the transmitting end antenna (1) is connected with the transmitting end of the antenna unit, and the receiving end antenna (2) is connected with the receiving end of the antenna unit.
4. The system of claim 1, wherein the system further comprises: the digital interference cancellation module comprises a nonlinear and phase noise interference reconstruction module, a linear digital interference reconstruction module and a fourth adder;
the input end of the fourth adder is respectively connected with the output end of the nonlinear and phase noise interference reconstruction module, the output end of the linear digital interference reconstruction module and the receiving end of the baseband signal processing unit, and the output end of the fourth adder is respectively connected with the input end of the baseband received signal processing unit, the input end of the nonlinear and phase noise interference reconstruction module and the input end of the linear digital interference reconstruction module;
the input end of the nonlinear and phase noise interference reconstruction module is also respectively connected with the output end of the signal pre-correction module, the output end of the baseband emission signal processing unit, the first feedback end of the baseband signal processing unit, the second feedback end of the baseband signal processing unit and the receiving end of the baseband signal processing unit;
the input end of the linear digital interference reconstruction module is also respectively connected with the output end of the signal pre-correction module, the output end of the baseband emission signal processing unit and the receiving end of the baseband signal processing unit.
5. The system of claim 1, wherein the system further comprises: the output end of the first adder is also connected with the input end of the radio frequency interference reconstruction unit.
6. The system of claim 1, wherein the system further comprises: the radio frequency interference reconstruction unit comprises a time delay adjusting module, an amplitude modulation module, a phase modulation module and a control module, wherein the control module is respectively connected with control ends of the time delay adjusting module, the amplitude modulation module and the phase modulation module which are sequentially connected in series, the input end of the time delay adjusting module is connected with the input end of the radio frequency interference reconstruction unit, and the output end of the phase modulation module is connected with the output end of the radio frequency interference reconstruction unit.
7. The system of claim 1, wherein the system further comprises: a first amplifier and a third analog-to-digital converter ADC III which are connected in series are further arranged between the second adder and the first feedback end of the baseband signal processing unit, and a second digital-to-analog converter DAC II is further arranged between the second adder and the output end of the first regulator module;
a second amplifier and a first analog-to-digital converter (ADC I) are also arranged between the third adder and the second feedback end of the baseband signal processing unit; and a fourth digital-to-analog converter DAC IV is also arranged between the third adder and the output end of the second regulator module.
8. The system of claim 1, wherein the system further comprises: a first digital-to-analog converter DAC I is arranged between the input end of the first radio frequency transmitting channel and the first transmitting end of the baseband signal processing unit;
a third digital-to-analog converter DAC III is arranged between the input end of the second radio frequency transmitting channel and the second transmitting end of the baseband signal processing unit;
and a second analog-to-digital converter ADC II is arranged between the output end of the first radio frequency receiving channel and the receiving end of the baseband signal processing unit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510262792.4A CN104954307B (en) | 2015-05-21 | 2015-05-21 | A kind of co-channel full duplex limit self-interference cancellation system simultaneously |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510262792.4A CN104954307B (en) | 2015-05-21 | 2015-05-21 | A kind of co-channel full duplex limit self-interference cancellation system simultaneously |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN104954307A CN104954307A (en) | 2015-09-30 |
| CN104954307B true CN104954307B (en) | 2018-04-10 |
Family
ID=54168667
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510262792.4A Active CN104954307B (en) | 2015-05-21 | 2015-05-21 | A kind of co-channel full duplex limit self-interference cancellation system simultaneously |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN104954307B (en) |
Families Citing this family (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105337720B (en) * | 2015-09-29 | 2018-08-03 | 电子科技大学 | A kind of simulation self-interference suppression circuit and self-interference suppressing method |
| CN106130594B (en) * | 2016-01-26 | 2018-08-17 | 西北工业大学 | Co-channel full duplex communication means and device while inhibition based on frequency domain self-interference |
| CN105915239B (en) * | 2016-06-17 | 2018-05-08 | 电子科技大学 | A kind of method that while co-channel full duplex system and its coupling are chosen with predistortion RF disturbance reconstruction port number |
| CN106130600B (en) * | 2016-06-22 | 2018-11-02 | 电子科技大学 | A kind of feedback reconstructing system of self-interference signal |
| CN108206734B (en) * | 2016-12-20 | 2020-09-08 | 北京大学 | Full-duplex self-interference elimination method based on SSK |
| CN108365863B (en) * | 2018-02-09 | 2021-10-22 | 沃勤科技有限公司 | Device and method for self-adaptively counteracting out-of-band interference received in wireless transceiving system |
| CN108768431A (en) * | 2018-04-21 | 2018-11-06 | 成都定为电子技术有限公司 | A kind of co-channel full duplex intercom and its implementation simultaneously |
| CN109274617B (en) * | 2018-09-14 | 2021-07-02 | 中国人民解放军国防科技大学 | Simultaneous same-frequency full-duplex measurement and control transponder |
| CN110061759B (en) * | 2019-04-26 | 2020-08-04 | 电子科技大学 | Electromagnetic spectrum umbrella cover radio frequency domain self-interference suppression method and system |
| CN114499558B (en) * | 2022-02-16 | 2024-01-16 | 成都市联洲国际技术有限公司 | Co-channel interference cancellation device |
| CN115021885B (en) * | 2022-05-19 | 2024-03-12 | 中国电子科技集团公司第三十六研究所 | In-band full duplex system and interference signal cancellation method thereof |
| CN117294411A (en) * | 2022-06-20 | 2023-12-26 | 中兴通讯股份有限公司 | Signal processing method, signal processing system, signal processing device, and storage medium |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103338172A (en) * | 2013-07-24 | 2013-10-02 | 电子科技大学 | Simultaneous common-frequency full duplex self-interference offset method in multi-path environment |
| CN103427872A (en) * | 2013-09-03 | 2013-12-04 | 电子科技大学 | Same-time same-frequency full duplex multi-tap radio frequency self-interference offset system and method |
| CN103427874A (en) * | 2013-09-03 | 2013-12-04 | 电子科技大学 | System and method for canceling high-transmission-power same-time same-frequency self-interference under multi-path environment |
| CN103580720A (en) * | 2013-11-20 | 2014-02-12 | 东南大学 | Same-frequency full-duplex self-interference offset device |
-
2015
- 2015-05-21 CN CN201510262792.4A patent/CN104954307B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103338172A (en) * | 2013-07-24 | 2013-10-02 | 电子科技大学 | Simultaneous common-frequency full duplex self-interference offset method in multi-path environment |
| CN103427872A (en) * | 2013-09-03 | 2013-12-04 | 电子科技大学 | Same-time same-frequency full duplex multi-tap radio frequency self-interference offset system and method |
| CN103427874A (en) * | 2013-09-03 | 2013-12-04 | 电子科技大学 | System and method for canceling high-transmission-power same-time same-frequency self-interference under multi-path environment |
| CN103580720A (en) * | 2013-11-20 | 2014-02-12 | 东南大学 | Same-frequency full-duplex self-interference offset device |
Non-Patent Citations (5)
| Title |
|---|
| "同时同频全双工LTE射频自干扰抑制能力分析及实验验证";徐强等;《电子与信息学报》;20140315;第36卷(第3期);第662-668页 * |
| "同时同频全双工场景中的射频域自适应干扰抵消";王俊等;《电子与信息学报》;20140615;第36卷(第6期);第1435-1440页 * |
| "多径瑞利衰落信道条件下射频干扰抵_省略_CCFD系统中OFDM性能的影响";何昭君等;《电子与信息学报》;20140215;第36卷(第2期);第358-363页 * |
| "室内环境下2_6GHz同时同频全双工自干扰信道测量与建模";吴翔宇等;《电子学报》;20150115;第43卷(第1期);第1-6页 * |
| "室内环境下共用收发天线同时同频全双工自干扰信道测量与建模";吴翔宇等;《系统工程与电子技术》;20150403;第36卷(第6期);第1435-1440页 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN104954307A (en) | 2015-09-30 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103338172B (en) | A kind of same-frequency full-duplex self-interference offset method while of under multi-path environment | |
| CN104935540B (en) | A kind of co-channel full duplex limit self-interference cancellation method simultaneously | |
| CN104954307B (en) | A kind of co-channel full duplex limit self-interference cancellation system simultaneously | |
| CN103427872B (en) | Same-time same-frequency full duplex multi-tap radio frequency self-interference offset system and method | |
| CN103427874B (en) | System and method for canceling high-transmission-power same-time same-frequency self-interference under multi-path environment | |
| CN107026673B (en) | Digital-assisted analog domain interference cancellation method and device | |
| US10230419B2 (en) | Adaptive techniques for full duplex communications | |
| US20070161361A1 (en) | Interference rejection in telecommunication system | |
| US10644814B2 (en) | Intermodulation byproduct cancellation in one or more nodes of a distributed antenna system | |
| CN104716980A (en) | Method for eliminating self interference of multiple same-time same-frequency full-duplex radio frequency sub bands | |
| CN110661546B (en) | Method and system for eliminating harmonic interference digital domain in 5G terminal based on NSA architecture | |
| US10432250B2 (en) | Method for cancelling self-interference of in-band full-duplex multiple-input multiple-output wireless communication | |
| US20170141836A1 (en) | Multi-antenna relay device | |
| KR20140145357A (en) | Two-way relay apparatus and method thereof | |
| CN101277480B (en) | Direct amplifier station eliminating self-excitation interference | |
| CN103516485A (en) | Signal receiving anti-interference processing method and device based on multiple antennas | |
| Antonio-Rodríguez et al. | Subspace-constrained SINR optimization in MIMO full-duplex relays under limited dynamic range | |
| CN114245996B (en) | Novel high-capacity communication system | |
| KR102382689B1 (en) | Method of in-band full-duplex multiple-input multiple-output transmission and reception, and apparatus for the same | |
| CN107408975B (en) | Digital repeater system and method | |
| CN107592149B (en) | Full-duplex filtering forwarding relay structure and discrete frequency domain response design method thereof | |
| Sornalatha et al. | Modeling of widely linear digitally controlled self-interference canceller for full-duplex transceiver | |
| KR102563345B1 (en) | Apparatus and method for wireless relaying | |
| KR102563334B1 (en) | Apparatus and method for wireless relaying | |
| CN116346151A (en) | Communication transceiver, signal transmitting/receiving method, electronic device, and storage medium |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |