METHOD AND DEVICE FOR REMOVING SELF-INTERFERENCE SIGNAL IN ENVIRONMENT USING FDR MODE

• US 20180013466A1
• Filed: 10/21/2015
• Published: 01/11/2018
• Est. Priority Date: 01/23/2015
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: KIM, Dongkyu, KO, Hyunsoo, CHUNG, Jaehoon, CHOI, Kukheon, NOH, Kwangseok, LEE, Sangrim
• Granted Patent: US 10,326,483 B2
• Time in Patent Office: Days
• CPC Class Codes: H04B 1/12 Neutralising, balancing, or compensation arrangements
• CPC Class Codes: H04B 1/525 with means for reducing leakage of transmitter signal into the receiver
• CPC Class Codes: H04B 1/56 with provision for simultaneous communication in two directions
• CPC Class Codes: H04B 15/02 Reducing interference from electric apparatus by means located at or near the interfering apparatus
• CPC Class Codes: H04B 17/14 of the whole transmission and reception path, e.g. self-test loop-back
• CPC Class Codes: H04B 17/345 Interference values signal-to-interference ratio [SIR] or carrier-to-interference ratio [CIR] H04B17/336
• CPC Class Codes: H04B 7/0857 using maximum ratio combining techniques, e.g. signal-to- interference ratio [SIR], received signal strenght indication [RSS]
• CPC Class Codes: H04L 1/00 Arrangements for detecting or preventing errors in the information received correcting synchronisation H04L7/00
• CPC Class Codes: H04L 1/12 by using return channel
• CPC Class Codes: H04L 5/0044 allocation of payload
• CPC Class Codes: H04L 5/0055 Physical resource allocation for ACK/NACK for physical mapping arrangements in ARQ protocols H04L1/1861
• CPC Class Codes: H04L 5/14 Two-way operation using the same type of signal, i.e. duplex
• CPC Class Codes: H04L 5/1461 Suppression of signals in the return path, i.e. bidirectional control circuits

Abstract

A method for removing a self-interference signal by a device supporting an FDR mode can further comprise the steps of: transmitting a signal to a counterpart node in a predetermined time interval; generating, in an RF stage of the device, a residual self-interference signal after removal of an analog self-interference signal with respect to the signal and then storing same; and receiving from the counterpart node a NACK signal with respect to the transmission of the signal; retransmitting the signal to the counterpart node; and, if decoding of the signal which has been received in the predetermined time interval is successful, using only a part of the stored residual self-interference signal when removing a digital self-interference signal on the basis of the retransmission.

Claims

1. A method for performing self-interference signal cancellation by a device supporting a full duplex communication (FDR) mode, the method comprising:

transmitting a signal to a target node in a predetermined time interval;

generating and storing a residual self-interference signal after cancelling an analog self-interference signal with respect to the signal at a radio frequency (RF) end of the device;

receiving a negative-acknowledgement (NACK) signal from the target node in response to the transmitted signal;

retransmitting the signal to the target node; and

when a signal received in the predetermined time interval is successfully decoded, using only a portion of the stored residual self-interference signal in cancelling a digital self-interference signal associated with the retransmission.

2. The method of claim 1, further comprising:

obtaining other portions except the portion of the stored residual self-interference signal through self-interference signal estimation associated with the retransmission.

3. The method of claim 1, wherein the portion of the stored self-interference signal includes coefficients of linear components in a channel of the stored self-interference signal and coefficients of non-linear components with orders equal to or lower than a predetermined order in the channel of the stored self-interference signal.

4. The method of claim 3, further comprising:

obtaining coefficients of non-linear components with orders higher than the predetermined order through self-interference signal estimation associated with the retransmission.

5. The method of claim 3, wherein the predetermined order is determined based on transmit power of the signal.

6. The method of claim 2, further comprising:

performing digital self-interference cancellation associated with the retransmission using the portion of the stored residual self-interference signal and the portions obtained through the self-interference signal estimation associated with the retransmission.

7. A device for performing self-interference signal cancellation, the device supporting a full duplex communication (FDR) mode, the device comprising:

a transmitter configured to transmit a signal to a target node in a predetermined time interval;

a radio frequency (RF) unit configured to generate and store a residual self-interference signal after cancelling an analog self-interference signal with respect to the signal at an RF end of the device; and

a receiver configured to receive a negative-acknowledgement (NACK) signal from the target node in response to the transmitted signal,

wherein the transmitter is configured to retransmit the signal to the target node, and

wherein when a signal received in the predetermined time interval is successfully decoded, the RF unit is configured to use only a portion of the stored residual self-interference signal in cancelling a digital self-interference signal associated with the retransmission.

8. The device of claim 7, further comprising:

a processor configured to obtain other portions except the portion of the stored residual self-interference signal through self-interference signal estimation associated with the retransmission.

9. The device of claim 7, wherein the portion of the stored self-interference signal includes coefficients of linear components in a channel of the stored self-interference signal and coefficients of non-linear components with orders equal to or lower than a predetermined order in the channel of the stored self-interference signal.

10. The device of claim 9, further comprising:

a processor configured to obtain coefficients of non-linear components with orders higher than the predetermined order through self-interference signal estimation associated with the retransmission.

11. The device of claim 9, further comprising:

a processor configured to determine the predetermined order based on transmit power of the signal.

12. The device of claim 8, wherein the RF unit is configured to perform digital self-interference cancellation associated with the retransmission using the portion of the stored residual self-interference signal and the portions obtained through the self-interference signal estimation