CN107872240B - Interference signal transmission and elimination method suitable for co-frequency simultaneous full duplex system - Google Patents

Interference signal transmission and elimination method suitable for co-frequency simultaneous full duplex system Download PDF

Info

Publication number
CN107872240B
CN107872240B CN201610841850.3A CN201610841850A CN107872240B CN 107872240 B CN107872240 B CN 107872240B CN 201610841850 A CN201610841850 A CN 201610841850A CN 107872240 B CN107872240 B CN 107872240B
Authority
CN
China
Prior art keywords
channel
interference
receiving end
interference signal
signal
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
Application number
CN201610841850.3A
Other languages
Chinese (zh)
Other versions
CN107872240A (en
Inventor
焦秉立
段晓辉
马猛
陈颖玚
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Peking University Information Technology Institute (tianjin Binhai)
Original Assignee
Peking University Information Technology Institute (tianjin Binhai)
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Peking University Information Technology Institute (tianjin Binhai) filed Critical Peking University Information Technology Institute (tianjin Binhai)
Priority to CN201610841850.3A priority Critical patent/CN107872240B/en
Publication of CN107872240A publication Critical patent/CN107872240A/en
Application granted granted Critical
Publication of CN107872240B publication Critical patent/CN107872240B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L5/00—Arrangements affording multiple use of the transmission path
    • H04L5/14—Two-way operation using the same type of signal, i.e. duplex
    • H04L5/1461—Suppression of signals in the return path, i.e. bidirectional control circuits
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/38—Transceivers, i.e. devices in which transmitter and receiver form a structural unit and in which at least one part is used for functions of transmitting and receiving
    • H04B1/40—Circuits
    • H04B1/50—Circuits using different frequencies for the two directions of communication
    • H04B1/52—Hybrid arrangements, i.e. arrangements for transition from single-path two-direction transmission to single-direction transmission on each of two paths or vice versa
    • H04B1/525—Hybrid arrangements, i.e. arrangements for transition from single-path two-direction transmission to single-direction transmission on each of two paths or vice versa with means for reducing leakage of transmitter signal into the receiver
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L1/00—Arrangements for detecting or preventing errors in the information received
    • H04L1/0001—Systems modifying transmission characteristics according to link quality, e.g. power backoff
    • H04L1/0009—Systems modifying transmission characteristics according to link quality, e.g. power backoff by adapting the channel coding
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L25/00—Baseband systems
    • H04L25/02—Details ; arrangements for supplying electrical power along data transmission lines
    • H04L25/0202—Channel estimation
    • H04L25/024—Channel estimation channel estimation algorithms
    • H04L25/025—Channel estimation channel estimation algorithms using least-mean-square [LMS] method
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L25/00—Baseband systems
    • H04L25/02—Details ; arrangements for supplying electrical power along data transmission lines
    • H04L25/03—Shaping networks in transmitter or receiver, e.g. adaptive shaping networks
    • H04L25/03006—Arrangements for removing intersymbol interference
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L25/00—Baseband systems
    • H04L25/02—Details ; arrangements for supplying electrical power along data transmission lines
    • H04L25/08—Modifications for reducing interference; Modifications for reducing effects due to line faults ; Receiver end arrangements for detecting or overcoming line faults

Abstract

The invention provides an interference signal transmission and elimination method suitable for a same-frequency simultaneous full-duplex system. The invention uses wire connection between the transmitting end and the receiving end to send the interference signal which is only coded by the source and not coded by the channel to the receiver. By arranging the signal preprocessing unit at the receiving end, the interference signal is processed by the channel encoder, the channel simulator and the adding unit respectively, and self-interference cancellation is completed. According to the invention, the interference signal is subjected to channel coding at the receiving end, so that the radio frequency interference signal can be reconstructed better, and the radio frequency self-interference cancellation performance is improved.

Description

Interference signal transmission and elimination method suitable for co-frequency simultaneous full duplex system
Technical Field
The invention relates to a method for removing interference in the field of wireless communication, in particular to a system and a method for eliminating interference of common-frequency simultaneous full duplex.
Background
A basic task of a wireless communication system is to establish a communication link between a wireless terminal and a base station. The transmission of data can be divided into two directions, namely: the link from the base station to the wireless terminal, called the downlink; the link from the wireless terminal to the base station is called the uplink. A system capable of implementing uplink and downlink data transmission is called a duplex system. Existing wireless communication systems all use two duplexing modes, time division duplexing and frequency division duplexing. Time division duplex systems use the same frequency to transmit data using different time slots to isolate interference between the uplink and downlink. Frequency division duplex systems use the same time slot to transmit data using different frequencies to isolate interference between the uplink and downlink. In the process of isolating uplink and downlink interference, the two duplex methods respectively sacrifice time resources and frequency resources, which results in low frequency spectrum utilization rate.
If the same frequency is used for simultaneous transceiving, the same-frequency simultaneous full-duplex technology is used for bidirectional communication, and the frequency spectrum efficiency is obviously improved. However, the same-frequency simultaneous full-duplex system has the problem of self-interference, and the establishment of an effective interference elimination method is beneficial to the realization of the performance of the same-frequency simultaneous full-duplex system.
Disclosure of Invention
The invention aims to provide a system and a method suitable for same-frequency simultaneous full-duplex self-interference cancellation.
The technical scheme of the invention is as follows:
in a communication system using co-frequency simultaneous full duplex transmission, a wireless terminal transmits a signal to a base station through an uplink, and interference at the base station mainly comes from self-interference of a base station transmitter to a base station receiver. To eliminate the interference, we add a signal pre-processing unit at the conventional receiver (as shown in fig. 1). An independent signal connection channel, i.e. a wired connection, is established between the signal preprocessing unit and the base station transmitter. By means of this wired connection, the interference signal is fed to the signal preprocessing unit to cancel it out from the interference signal from the air interface.
In order to better reconstruct the interference signal at the receiving end of the base station, the transmitting end transmits the signal which is only subjected to source coding and is not subjected to channel coding to the receiving end through a wired connection. Particularly, the signal without channel coding has the characteristic of low redundancy, and has the advantage of high spectrum efficiency in wired transmission, so that the self-interference signal received at the receiving end has high reliability, and the reconstruction of the air interference signal is facilitated.
Because the wired channel and the air interface channel received and transmitted by the base station have larger difference, the signal preprocessing unit at the receiving end is used for reconstructing interference signals. Firstly, a channel encoder performs channel encoding on an interference signal acquired from a wired connection channel; the channel simulator then estimates the channel parameters between the base station receiver and the base station transmitter, and the specific estimation method may use any existing channel estimation method, such as: pilot assisted minimum mean square error estimation. The channel simulator simulates the interference transmitter signal output by the channel encoder as an air interference signal received by the receiver by using the estimated channel parameter, and in a subsequent adding unit, the output signal of the channel simulator is subtracted from the interference signal actually received by the receiver, namely, the self-interference at the receiver of the full-duplex base station is eliminated.
Drawings
Fig. 1 is a schematic diagram of a method for eliminating interference of a co-frequency simultaneous full-duplex base station.
Detailed Description
The technical solutions of the present invention are further described in detail below with reference to the accompanying drawings, but the scope of the present invention is not limited to the following.
As shown in fig. 1, the key to implementing the above interference cancellation technique is that the receiving end performs channel coding on the interference signal and performs channel simulation accurately. Before sending an interference signal to a receiving end, a transmitting end needs to inform the receiving end of a channel coding scheme adopted by the receiving end. If the channel coding of the transmitting terminal is self-adaptive, informing the receiving terminal of a new channel coding mode when the downlink channel state information changes every time, and then sending an interference signal which is only subjected to source coding and is not subjected to channel coding; if the transmitting end adopts a fixed channel coding mode, the receiving end is informed once before the interference signal is sent. After receiving the channel coding information, the receiving end uses the channel coder to perform channel coding on the sent interference signal. The channel simulator converts the interference signal after channel coding to approximately coincide with the interference signal on the air interface, and eliminates the interference in the signal received by the receiver as much as possible by using subtraction. The method for obtaining the interference channel parameters may be: special narrow time slots with equal intervals are firstly established on a time domain through a system protocol, in the special time slots, all wireless terminals stop signal transmission, and only a base station transmitter transmits signals. At the receiver end of the base station, the channel parameters can be estimated using the signals received by the receiving antennas and the interference signals transmitted by the wired connection.

Claims (6)

1. A method for transmitting and eliminating interference signals suitable for a co-frequency simultaneous full duplex system is characterized in that at a transmitting end of the full duplex system, low redundancy interference signals which are not subjected to channel coding are transmitted to a receiving end by utilizing wired connection, and a signal preprocessing unit is arranged at a receiver to perform channel coding and channel simulation on the interference signals and reconstruct air interference signals, so that the air interference signals and the interference signals from an air interface are mutually offset; before sending an interference signal to a receiving end, a transmitting end needs to inform the receiving end of a channel coding scheme adopted by the receiving end; if the channel coding of the transmitting terminal is self-adaptive, informing the receiving terminal of a new channel coding mode when the downlink channel state information changes every time, and then sending an interference signal which is only subjected to source coding and is not subjected to channel coding; if the transmitting end adopts a fixed channel coding mode, the receiving end is informed once before the interference signal is sent.
2. The method of claim 1, wherein the wired connection is a separate microwave connection.
3. The method as claimed in claim 1, wherein the signal preprocessing unit performs channel coding on the interference signal received from the wired connection, then the channel simulator estimates the channel parameter or the inverse number of the channel parameter between the receiving end and the transmitting end, then the estimated value of the channel parameter or the inverse number thereof and the interference signal after channel coding are used to recover the interference signal received by the receiving end or the inverse number thereof, and the interference signal is subtracted or added with the received signal, thereby eliminating the interference of the transmitting end to the receiving end.
4. The method according to claim 3, wherein the channel simulator performs channel estimation by setting narrow time slots at equal intervals in the time domain through a system protocol, and in the special time slots, all wireless terminals stop signal transmission and only the base station transmitting end transmits interference signals; the receiving end estimates the channel parameter from the transmitting end to the receiving end after channel coding by using the signal received by the receiving antenna and the interference signal transmitted by the wired connection.
5. The method as claimed in claim 3, wherein the channel simulator performs channel estimation using pilot-assisted least mean square error estimation.
6. The method as claimed in claim 1, wherein the source coding and channel coding modules are disposed on the baseband circuit, and the channel simulator is disposed on the rf circuit.
CN201610841850.3A 2016-09-23 2016-09-23 Interference signal transmission and elimination method suitable for co-frequency simultaneous full duplex system Active CN107872240B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201610841850.3A CN107872240B (en) 2016-09-23 2016-09-23 Interference signal transmission and elimination method suitable for co-frequency simultaneous full duplex system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201610841850.3A CN107872240B (en) 2016-09-23 2016-09-23 Interference signal transmission and elimination method suitable for co-frequency simultaneous full duplex system

Publications (2)

Publication Number Publication Date
CN107872240A CN107872240A (en) 2018-04-03
CN107872240B true CN107872240B (en) 2020-04-07

Family

ID=61751038

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201610841850.3A Active CN107872240B (en) 2016-09-23 2016-09-23 Interference signal transmission and elimination method suitable for co-frequency simultaneous full duplex system

Country Status (1)

Country Link
CN (1) CN107872240B (en)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
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
CN114070420B (en) * 2020-07-31 2023-04-07 华为技术有限公司 Anti-interference electronic equipment and anti-interference method
CN112821903B (en) * 2020-12-30 2022-09-16 天津师范大学 Simultaneous same-frequency full-duplex self-adaptive digital self-interference elimination time slot selection method
CN116054875B (en) * 2023-03-29 2023-06-06 深圳鹏龙通科技有限公司 MIMO transceiver supporting full duplex mode switching

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7010053B2 (en) * 2000-11-06 2006-03-07 Hesham El-Gamal Method and system for utilizing space-time and space-frequency codes for multi-input multi-output frequency selective fading channels
US7680212B2 (en) * 2004-08-17 2010-03-16 The Board Of Trustees Of The Leland Stanford Junior University Linear precoding for multi-input systems based on channel estimate and channel statistics
CN101141235B (en) * 2006-09-08 2011-11-09 北京大学 Interference canceling method for co-frequency co-time slot duplexing
CN101162961B (en) * 2006-10-12 2012-09-26 北京三星通信技术研究有限公司 Method and system of preventing co-channel interference
FR2938140B1 (en) * 2008-10-31 2011-04-15 St Microelectronics Sa INTERFERENCE REMOVAL RECEIVER BETWEEN CARRIERS.
CN103200140B (en) * 2012-01-06 2016-05-11 微思泰（北京）信息技术有限公司 A kind of interference cancelling system and method based on preequalization
CN104617981B (en) * 2015-01-19 2017-03-29 厦门大学 A kind of full duplex self-interference removing method and device based on Power estimation

Also Published As

Publication number Publication date
CN107872240A (en) 2018-04-03

Similar Documents

Publication Publication Date Title
CN107872240B (en) Interference signal transmission and elimination method suitable for co-frequency simultaneous full duplex system
WO2018174641A3 (en) Method and apparatus for transmitting data in wireless communication system
CN106464626B (en) Data transmission method and device between baseband unit BBU and remote radio unit RRU
CN106209151B (en) Full duplex self-interference eliminates wireless signal receive-transmit system and wireless signal receiving/transmission method
CN103458424A (en) Self-interference elimination method based on power detection and loop delay calculation
CN112134656B (en) D2D-NOMA cooperative communication system based on partial decoding forwarding
GB2575910A (en) Communication network with control plane network
CN110601738A (en) Frequency spectrum sharing-based rate analysis method for environment backscatter array communication system
WO2017075489A1 (en) Selection of decoding level at signal forwarding devices
KR20140145357A (en) Two-way relay apparatus and method thereof
KR20100089166A (en) Apparatus and method for interference cancellation in mobile full duplex relay
CN104754537B (en) Method and device for sending and receiving network auxiliary signaling
CN101478512B (en) Data precoding method for MIMO wireless communication system
KR102314459B1 (en) Method and apparatus for controlling interference in mobile communication system
CN105246110A (en) Wireless communication extension for CAN based electrical architectures
KR101386654B1 (en) Full-duplex mimo relay apparatus and method
CN109560844B (en) Multi-user relay transmission method based on non-orthogonal multiple access technology
WO2017114053A1 (en) Method and apparatus for signal processing
CN208143221U (en) A kind of radio communication relay
KR101561740B1 (en) Method for cancelling inter-subcarrier interference in distributed antenna systems and apparatus for performing the same
CN107017928B (en) Preprocessing method for suppressing cross polarization interference based on oblique projection
CN205195736U (en) Full duplex system from interference elimination device and basic station local system
CN116418365A (en) Modulator-demodulator based on in-band frequency hopping system
TWI611681B (en) Full-duplex radio receiver network device and full-duplex radio data transmission method thereof
KR102573992B1 (en) Apparatus and method for generating and transmitting cqi in a wireless network

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant