Method and apparatus for interference cancellation in full-duplex multi-cell networks

Patent metadata

Field	Value
Publication number	US-10320431-B2
Application number	US-201715661541-A
Country	US
Kind code	B2
Filing date	Jul 27, 2017
Priority date	Jul 27, 2017
Publication date	Jun 11, 2019
Grant date	Jun 11, 2019

Abstract

Techniques and architectures for multi-stage cancellation of self-interference (SI) and joint cancellation of mutual-interference (MI) and residual SI in signals received by devices of a full-duplex multi-cell network are disclosed. In various examples, channel estimations and interference cancellation operations are performed utilizing multiple orthogonal training signals transmitted by network devices during a common over-the-air training period. Training signals derived from the orthogonal training signals during transmission are utilized to generate SI estimation information and perform at least a first SI cancellation operation on a received signal that includes at least first and second orthogonal training signals. The received signal and orthogonal training signals are then used to estimate a MI channel impulse response and a (residual) SI channel impulse response for use in joint MI/SI cancellation operations on further received signals. Details regarding the design of the orthogonal training signals and a unique system-level delay calibration procedure are also provided.

First claim

What is claimed is:

1. A method for cancelling self interference (SI) and mutual interference (MI) in signals received by a local full-duplex transmit/receive point (TRP) having at least one transmit and receive antenna, the method comprising:
determining a first orthogonal training signal from a plurality of orthogonal training signals, each transmit antenna of the local TRP having a unique orthogonal training signal;
mapping the first orthogonal training signal to a transmit antenna of the TRP;
transmitting the first orthogonal training signal via the transmit antenna;
receiving, by a receive antenna of the TRP, a signal including the first orthogonal training signal and at least a second orthogonal training signal from the plurality of orthogonal training signals, the second orthogonal training signal originating from a remote TRP;
performing a local TRP first stage SI cancellation operation on the received signal containing the first and second orthogonal signals, the local TRP first stage SI cancellation operation performed in accordance with a non-orthogonal training signal determined in accordance with the first orthogonal training signal and the transmitting of the first orthogonal training signal, to generate first stage SI estimation information and cancel a first stage SI component of the received signal;
generating an estimate of a first channel impulse response (CIR) of a wireless channel between the transmit antenna and the receive antenna, the generated first CIR estimate determined in accordance with the received signal and the first orthogonal training signal, the first CIR relating to the residue of the SI component of the received signal after the first stage SI cancellation; and
generating an estimate of a second CIR of a wireless channel between the local TRP and the remote TRP for MI cancellation, the generated second CIR estimate determined in accordance with the received signal and transmission information related to the second orthogonal training signal.

2. The method of claim 1 , further comprising:
receiving, at the receive antenna of the local TRP, a data signal;
performing a SI cancellation operation on the received data signal, the SI cancellation operation utilizing the first stage SI estimation information;
determining a residual SI component of the received data signal based on the first CIR and data transmitted by the transmit antenna of the local TRP;
determining a MI component of the received data signal based on the second CIR and data transmitted by the remote TRP; and
cancelling the residual SI component and the MI component of the received data signal.

3. The method of claim 1 , further comprising:
prior to generating the first and second CIR estimates, performing the first stage SI cancellation operation on the received signal to generate the non-orthogonal training signal SI estimation information and cancel the first stage SI component of the received signal, the first stage SI cancellation operation utilizing a further non-orthogonal training signal determined in accordance with the first orthogonal training signal.

4. The method of claim 1 , further comprising:
transmitting, via the transmit antenna, a first calibration training signal during a first calibration period;
receiving, via the receive antenna, a second calibration training signal transmitted by the remote TRP during a second calibration period; and
generating an estimate of a propagation delay value relating to the wireless channel between the local TRP and the remote TRP, based on the received second calibration training signal.

5. The method of claim 4 , wherein estimating the first CIR and the second CIR is further based on the propagation delay value.

6. The method of claim 1 , wherein the plurality of orthogonal training signals comprises zero correlation zone (ZCZ) sequences.

7. The method of claim 1 , wherein the plurality of orthogonal training signals comprises Zadoff-Chu sequences modulated with blocks of random phase rotations.

8. The method of claim 1 , wherein the determining of the first orthogonal training signal includes assignments by a centralized-radio access network (C-RAN) to the TRPs.

9. The method of claim 1 , wherein the transmitting of the first orthogonal training signal via the transmit antenna occurs, at least in part, during a training portion of a subframe comprising a downlink portion, the training portion, and an uplink portion.

10. A method for cancelling self interference (SI) and mutual interference (MI) in signals received by a full-duplex transmit/receive point (TRP) having at least one pair of transmit and receive antennae, the method comprising:
determining a plurality of orthogonal training signals including at least a first orthogonal training signal for a local TRP and at least a second orthogonal training signal for remote TRP;
mapping the first orthogonal training signal to a transmit antenna of a first local TRP;
mapping the second orthogonal training signal to a transmit antenna of a second remote TRP;
communicating the first orthogonal training signal and the second orthogonal training signal to the first TRP and the second TRP, respectively, for concurrent transmission during a same training signal period;
receiving, from the first TRP, a non-orthogonal training signal determined in accordance with the first orthogonal training signal;
receiving, from the first TRP, a signal including the first orthogonal training signal and the second orthogonal training signal as received by a receive antenna of the first TRP;
performing a first stage SI cancellation operation on the received signal to generate first stage SI estimation information and cancel a first SI component of the received signal, the first stage SI cancellation operation utilizing the non-orthogonal training signal;
generating an estimate of a first channel impulse response (CIR) of a wireless channel between the transmit antenna and the receive antenna, the generated first CIR estimate determined in accordance with the first stage non-orthogonal training signal cancelled residue received signal and the first orthogonal training signal; and
generating an estimate of a second CIR of a wireless channel between the local TRP and the remote TRP for MI cancellation, the generated second CIR estimate determined in accordance with the first stage non-orthogonal SI cancelled residue received signal and the first orthogonal training signal.

11. The method of claim 10 , further comprising:
receiving, from the first TRP, a data signal;
performing a SI cancellation operation on the received data signal, the SI cancellation operation utilizing the first non-orthogonal training signal SI estimation information;
determining a residual SI component of the received data signal based on the first orthogonal training signal CIR and data transmitted by the transmit antenna of the first TRP;
determining a MI component of the received data signal based on the second orthogonal training signal CIR and data transmitted by the second TRP; and
cancelling the residual SI component and the MI component of the received data signal.

12. The method of claim 10 , further comprising:
receiving, from the first TRP, a non-orthogonal training signal determined in accordance with the first orthogonal training signal, wherein the first stage SI cancellation operation further utilizes the non-orthogonal training signal determined in accordance with the first TRP orthogonal training signal.

13. The method of claim 10 , further comprising:
performing a calibration procedure to generate propagation delay estimates for signals communicated between th

Assignees

• Huawei Tech Co Ltd

Inventors

• Wu Huan
• Hum Eddy Shi Ning
• Shiu Wan Yi

Classifications

• H04L5/0091

  Signalling for the administration of the divided path, e.g. signalling of configuration information · CPC title

• H04B1/56

  with provision for simultaneous communication in two directions · CPC title

• H04L25/0224

  using sounding signals · CPC title

• H04L25/0204

  of multiple channels · CPC title

• H04J13/0062

  Zadoff-Chu · CPC title