Full-duplex wireless communication method, antenna device and full-duplex wireless communication system

• US 9,912,374 B2
• Filed: 12/03/2015
• Issued: 03/06/2018
• Est. Priority Date: 08/18/2015
• Status: Expired due to Fees

• Current Assignee: Beijing University of Science and Technology
• Original Assignee: Beijing University of Science and Technology
• Inventors: Zhang, Zhongshan
• Primary Examiner(s): Patel, Parth
• Application Number:
  US14/957,706
• Publication Number:
  US 20170054472A1
• Time in Patent Office: 824 Days
• CPC Class Codes: H04B 3/238 using initial training sequence
• CPC Class Codes: H04L 5/143 for modulated signals H04L5/1469 takes precedence
• CPC Class Codes: H04L 5/1461 Suppression of signals in the return path, i.e. bidirectional control circuits

Abstract

The present disclosure provides a full-duplex wireless communication method, an antenna device and a full-duplex wireless communication system. The method includes steps of: within a training period, acquiring a relevant parameter for cancelling a self-interference signal from an antenna itself as a first estimated value, and a relevant parameter for cancelling a cross-interference signal between the antenna and the other antenna as a second estimated value; and within a data transmission period, receiving and transmitting signals simultaneously by the antenna using an identical frequency, cancelling the self-interference signal from the antenna itself in accordance with the first estimated value, and cancelling the cross-interference signal between the antenna and the other antenna in accordance with the second estimated value.

Claims

1. A full-duplex wireless communication method, comprising steps of:

within a training period, acquiring a relevant parameter for cancelling a self-interference signal from an antenna itself as a first estimated value, and a relevant parameter for cancelling a cross-interference signal between the antenna and the other antenna as a second estimated value; and

within a data transmission period, receiving and transmitting signals simultaneously by the antenna using an identical frequency, cancelling the self-interference signal from the antenna itself in accordance with the first estimated value, and cancelling the cross-interference signal between the antenna and the other antenna in accordance with the second estimated value,

wherein the step of, within the training period, acquiring the relevant parameter for cancelling the self-interference signal from the antenna itself as the first estimated value, and the relevant parameter for cancelling the cross-interference signal between the antenna and the other antenna as the second estimated value comprises;

in one of a plurality of training slots within the training period, transmitting, by the antenna, a predetermined training sequence and receiving the predetermined training sequence transmitted by itself, and in the other training slots, receiving, by the antenna, a predetermined training sequence from the other antenna; and

in the training slot, acquiring, by the antenna, the relevant parameter for cancelling the self-interference signal from the antenna itself as the first estimated value in accordance with the predetermined training sequence from the antenna itself, and within the other training slots, acquiring, by the antenna, the relevant parameter for cancelling the cross-interference signal between the antenna and the other antenna as the second estimated value in accordance with the predetermined training sequence from the other antenna;

wherein the step of, in the training slot, acquiring, by the antenna, the relevant parameter for cancelling the self-interference signal from the antenna itself as the first estimated value in accordance with the predetermined training sequence from the antenna itself comprises;

in the training slot, performing estimation, by the antenna, on a channel parameter of the self-interference signal at an analog domain in accordance with the predetermined training sequence from the antenna itself so as to obtain a first analog estimated value, and cancelling the self-interference signal from the antenna itself at the analog domain in accordance with the first analog estimated value; and

in the training slot, performing estimation, by the antenna, on a channel parameter of a residual self-interference signal at a digital domain in accordance with the residual self-interference signal from the antenna obtained after the analog-domain cancellation so as to obtain a first digital estimated value, and cancelling the residual self-interference signal from the antenna at the digital domain in accordance with the first digital estimated value;

wherein the step of, in the other training slots, acquiring, by the antenna, the relevant parameter for cancelling the cross-interference signal between the antenna and the other antenna as the second estimated value in accordance with the predetermined training sequence from the other antenna comprises;

in the other training slots, performing estimation, by the antenna, on a channel parameter of the cross-interference signal between the antenna and the other antenna at the analog domain in accordance with the predetermined training sequence from the other antenna so as to obtain a second analog estimated value, and cancelling the cross-interference signal between the antenna and the other antenna at the analog domain in accordance with the second analog estimated value; and

in the other training slots, performing estimation, by the antenna, on a channel parameter of a residual cross-interference signal between the antenna and the other antenna at the digital domain in accordance with a digital signal of the residual cross-interference signal between the antenna and the other antenna obtained after the analog cancellation so as to obtain a second digital estimated value, and cancelling the residual cross-interference signal between the antenna and the other antenna at the digital domain in accordance with the second digital estimated value.

2. The full-duplex wireless communication method according to claim 1, further comprising steps of:

in the training slot, transmitting, by the antenna, the predetermined training sequence periodically;

performing estimation, by the antenna that receives the predetermined training sequence, on the channel parameter of the self-interference signal from the antenna itself in accordance with the predetermined training sequence so as to obtain a plurality of first candidate estimated values, and performing estimation on the channel parameter of the cross-interference signal between the antenna and the other antenna in accordance with the predetermined training sequence so as to obtain a plurality of second candidate estimated values; and

selecting, by the antenna, an estimated value capable of enabling the energy of the residual self-interference signal to be minimum from the plurality of first candidate estimated values as the first estimated value, and selecting an estimated value capable of enabling the energy of the residual cross-interference signal to be minimum from the plurality of second candidate estimated values as the second estimated value.

3. The full-duplex wireless communication method according to claim 2, wherein an optimal value is determined, through negative feedback control, from the plurality of candidate estimated values as the first estimated value or the second estimated value, and the optimal value is an estimated value capable of enabling the signal power obtained after the addition to be minimum.

4. The full-duplex wireless communication method according to claim 1, wherein the step of cancelling, by the antenna, the self-interference signal from the antenna itself in accordance with the first estimated value comprises:

within the data transmission period, cancelling, by the antenna, the self-interference signal from the antenna itself at the analog domain in accordance with the first analog estimated value; and

cancelling, by the antenna, the residual self-interference signal from the antenna itself obtained after the analog-domain cancellation at the digital domain in accordance with the first digital estimated value.

5. The full-duplex wireless communication method according to claim 4, wherein the step of cancelling, by the antenna, the cross-interference signal between the antenna and the other antenna in accordance with the second estimated value comprises:

within the data transmission period, cancelling, by the antenna, the cross-interference signal between the antenna and the other antenna at the analog domain in accordance with the second analog estimated value; and

cancelling, by the antenna, the residual cross-interference signal between the antenna and the other antenna obtained after the analog-domain cancellation at the digital domain in accordance with the second digital estimated value.

6. The full-duplex wireless communication method according to claim 1, wherein in the training period, the cancellation step at the analog domain comprises:

inverting a phase of an analog signal of the predetermined training sequence from an transmitting antenna, so as to obtain an interference cancellation signal with a phase reverse to the analog signal,

acquiring an interference signal received by a receiving antenna and generated by the predetermined training sequence from the transmitting antenna;

comparing power of the interference cancellation signal and power of the interference signal, and adjusting the power of the interference cancellation signal in accordance with a comparison result, so as to enable a difference between the power of the interference cancellation signal and the power of the interference signal to be minimum; and

adding the interference cancellation signal to the interference signal, and adjusting the phase of the interference cancellation signal in accordance with an addition result, so as to enable the phase of the interference cancellation signal to be reverse to the phase of the interference signal and enable signal power obtained after the addition to approximate to be zero, thereby to perform the interference cancellation at the analog domain.

7. An antenna device, comprising:

a parameter estimation circuit configured to, within a training period, acquire a relevant parameter for cancelling a self-interference signal from an antenna itself as a first estimated value, and a relevant parameter for cancelling a cross-interference signal between the antenna and the other antenna as a second estimated value; and

an interference cancellation circuit configured to, within a data transmission period, cancel the self-interference signal from the antenna itself in accordance with the first estimated value and cancel the cross-interference signal between the antenna and the other antenna in accordance with the second estimated value when signals are received and transmitted simultaneously by the antenna using an identical frequency;

wherein the parameter estimation circuit comprises;

a training sequence transmission and reception circuit configured to, in one of a plurality of training slots within the training period, transmit a predetermined training sequence by the antenna itself and receive the predetermined training sequence from the antenna itself, and receive, in the other training slots, a predetermined training sequence from the other antenna; and

a parameter estimation sub-circuit configured to, in the training slot, acquire the relevant parameter for cancelling the self-interference signal from the antenna itself as the first estimated value in accordance with the predetermined training sequence from the antenna itself, and in the other training slots, acquire the relevant parameter for cancelling the cross-interference signal between the antenna and the other antenna as the second estimated value in accordance with the predetermined training sequence from the other antenna;

wherein the parameter estimation sub-circuit comprises;

a first analog estimation unit configured to, in the training slot, perform estimation on a channel parameter of the self-interference signal at an analog domain in accordance with the predetermined training sequence from the antenna itself so as to obtain a first analog estimated value, thereby to cancel the self-interference signal from the antenna itself at the analog domain in accordance with the first analog estimated value; and

a first digital estimation unit configured to, in the training slot, perform estimation on a channel parameter of a residual self-interference signal at a digital domain in accordance with the residual self-interference signal from the antenna obtained after the analog-domain cancellation so as to obtain a first digital estimated value, thereby to cancel the residual self-interference signal from the antenna at the digital domain in accordance with the first digital estimated value;

wherein the parameter estimation sub-circuit further comprises;

a second analog estimation unit configured to, in the other training slots, perform estimation on a channel parameter of the cross-interference signal between the antenna and the other antenna at the analog domain in accordance with the predetermined training sequence from the other antenna so as to obtain a second analog estimated value, thereby to cancel the cross-interference signal between the antenna and the other antenna at the analog domain in accordance with the second analog estimated value; and

a second digital estimation unit configured to, in the other training slots, performing estimation on a residual cross-interference signal between the antenna and the other antenna at the digital domain in accordance with the residual cross-interference signal between the antenna and the other antenna obtained after the analog cancellation so as to obtain a second digital estimated value, thereby to cancel the residual cross-interference signal between the antenna and the other antenna at the digital domain in accordance with the second digital estimated value.

8. The antenna device according to claim 7, wherein the sequence transmission and reception circuit includes a sequence transmission sub-circuit configured to, in the training slot, transmit the predetermined training sequence periodically, and

the parameter estimation sub-circuit comprises:

an estimation unit configured to perform estimation on the channel parameter of the self-interference signal from the antenna itself in accordance with the predetermined training sequence so as to obtain a plurality of first candidate estimated values, and performing estimation on the channel parameter of the cross-interference signal between the antenna and the other antenna in accordance with the predetermined training sequence so as to obtain a plurality of second candidate estimated values; and

a selection unit configured to select an estimated value capable of enabling the energy of the residual self-interference signal to be minimum from the plurality of first candidate estimated values as the first estimated value, and select an estimated value capable of enabling the energy of the residual cross-interference signal to be minimum from the plurality of second candidate estimated values as the second estimated value.

9. The antenna device according to claim 8, wherein an optimal value is determined, through negative feedback control, from the plurality of candidate estimated values as the first estimated value or the second estimated value, and the optimal value is an estimated value capable of enabling the signal power obtained after the addition to be minimum.

10. The antenna device according to claim 7, wherein the interference cancellation circuit comprises:

a first analog cancellation unit configured to, within the data transmission period, cancel the self-interference signal from the antenna itself at the analog domain in accordance with the first analog estimated value; and

a first digital cancellation unit configured to cancel the residual self-interference signal from the antenna itself obtained after the analog-domain cancellation at the digital domain in accordance with the first digital estimated value.

11. The antenna device according to claim 10, wherein the interference cancellation circuit further comprises:

a second analog cancellation unit configured to, within the data transmission period, cancel the cross-interference signal between the antenna and the other antenna at the analog domain in accordance with the second analog estimated value; and

a second digital cancellation unit configured to cancel the residual cross-interference signal between the antenna and the other antenna obtained after the analog-domain cancellation at the digital domain in accordance with the second digital estimated value.

12. The antenna device according to claim 7, further comprising:

an inversion circuit configured to, within the training period, invert a phase of an analog signal of the predetermined training sequence from the antenna, so as to obtain an interference cancellation signal with a phase reverse to the analog signal;

an acquisition circuit configured to acquire an interference signal generated by the predetermined training sequence;

a power comparison circuit configured to compare power of the interference cancellation signal and power of the interference signal, and adjust the power of the interference cancellation signal in accordance with a comparison result, so as to enable a difference between the power of the interference cancellation signal and the power of the interference signal to be minimum; and

a phase comparison circuit configured to add the interference cancellation signal to the interference signal, and adjust the phase of the interference cancellation signal in accordance with an addition result, so as to enable the phase of the interference cancellation signal to be reverse to the phase of the interference signal and enable signal power obtained after the addition to approximate to be zero, thereby to perform the interference cancellation at the analog domain.

13. A full-duplex wireless communication system, comprising N antenna devices according claim 7, wherein N is an integer greater than or equal to 1.