TECHNIQUE FOR FULL DUPLEX WITH SINGLE ANTENNA

• US 20170358857A1
• Filed: 02/16/2017
• Published: 12/14/2017
• Est. Priority Date: 06/13/2016
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Toshiba Corporation
• Inventors: WATKINS, Gavin
• Granted Patent: US 10,644,394 B2
• Time in Patent Office: Days
• CPC Class Codes: H01Q 1/525 between emitting and receiving antennas
• CPC Class Codes: H01Q 21/00 Antenna arrays or systems arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system H01Q3/00
• CPC Class Codes: H01Q 3/26 varying the relative phase or relative amplitude of energisation between two or more active radiating elements; varying the distribution of energy across a radiating aperture H01Q3/12, H01Q3/22, H01Q3/24 take precedence
• CPC Class Codes: H04B 1/56 with provision for simultaneous communication in two directions
• CPC Class Codes: H04B 1/58 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
• CPC Class Codes: H04L 5/14 Two-way operation using the same type of signal, i.e. duplex

Abstract

A system and method for duplexing radio frequency signals for full-duplex transmission and reception by an antenna. The system comprises a signal coupler comprising an antenna node configured to be connected to the antenna, an input node for receiving radio frequency signals for transmission by the antenna, an output node for outputting radio frequency signals received by the antenna, and a coupling node. The system further comprises a variable impedance element connected to the coupling node to reduce interference between the signals for transmission by the antenna and the signals received by the antenna, the variable impedance element comprising a variable phase shifter connected to a variable attenuator.

Claims

1. A system for duplexing radio frequency signals for full-duplex transmission and reception by an antenna, the system comprising:

a signal coupler comprising;

an antenna node configured to be connected to the antenna;

an input node for receiving radio frequency signals for transmission by the antenna;

an output node for outputting radio frequency signals received by the antenna; and

a coupling node; and

a variable impedance element connected to the coupling node to reduce interference between the signals for transmission by the antenna and the signals received by the antenna, the variable impedance element comprising a variable phase shifter connected to a variable attenuator.

2. A system according to claim 1 wherein the variable phase shifter comprises a set of switchable variable phase shifting elements configured to be switched to increase or decrease the phase shift across the variable phase shifter and/or the variable attenuator comprises a set of switchable variable attenuating elements configured to be switched to increase or decrease the attenuation across the variable attenuator.

3. A system according to claim 1 wherein the system is configured to adjust the impedance of the variable impedance element to reduce interference between the signals for transmission by the antenna and the signals received by the antenna.

4. A system according to claim 1 wherein the system comprises one or more further variable impedance elements and wherein the variable impedance element and the one or more further variable impedance elements are connected to the coupling terminal via a power splitter.

5. A multiple-input and multiple-output system for duplexing radio frequency signals, the system comprising a plurality of systems according to claim 1 wherein the systems are connected to each other via a common node connected to the coupling node of each system.

6. The multiple-input and multiple-output system of claim 5 wherein one or more of the systems have a variable impedance element located between the coupling node for the respective system and the common node.

7. The multiple-input and multiple-output system of claim 5 wherein each of the systems has a variable impedance element located between the coupling node for the respective system and the common node.

8. A device for wireless communication comprising:

a system according to claim 1;

an antenna connected to the antenna node of the signal coupler for full duplex wireless communication; and

a controller configured to;

provide the signals for transmission by the antenna to the input node of the signal coupler;

receive from the output node of the signal coupler the signals received by the antenna; and

control the variable impedance element to reduce interference between the signals for transmission by the antenna and the signals received by the antenna.

13. A multiple-input and multiple-output method for duplexing signals, the method comprising connecting a plurality of systems according to claim 1 to each other via a common node connected to the coupling node of each system.

14. The multiple-input and multiple-output method of claim 13 wherein one or more of the systems are connected to the coupling node via a variable impedance element located between the coupling node for the respective system and the common node.

15. The multiple-input and multiple-output method of claim 13 wherein each of the systems is connected to the coupling node via a respective variable impedance element located between the coupling node for the respective system and the common node.

9. A method for duplexing radio frequency signals for full-duplex transmission and reception by an antenna, the method being performed by a system comprising a signal coupler comprising an antenna node configured to be connected to the antenna, an input node, an output node and a coupling node, and a variable impedance element connected to the coupling node, the variable impedance element comprising a variable phase shifter and a variable attenuator, the method comprising:

receiving at the input node radio frequency signals for transmission by the antenna and outputting the signals for transmission at the antenna node;

receiving at the antenna node radio frequency signals received by the antenna and outputting the signals received by the antenna at the output node; and

applying a variable impedance to the coupling node via the variable impedance element to reduce interference between the signals for transmission by the antenna and the signals received by the antenna.

10. A method according to claim 9 wherein the variable phase shifter comprises a set of switchable variable phase shifting elements configured to be switched to increase or decrease the phase shift across the variable phase shifter and/or the variable attenuator comprises a set of switchable variable attenuating elements configured to be switched to increase or decrease the attenuation across the variable attenuator.

11. A method according to claim 9 wherein the method further comprises adjusting the impedance of the variable impedance element to reduce interference between the signals for transmission by the antenna and the signals received by the antenna.

12. A method according to claim 9 wherein the system comprises one or more further variable impedance elements, the variable impedance element and the one or more further variable impedance elements are connected to the coupling terminal via a power splitter, and the method further comprises applying one or more further variable impedances to the coupling node via the one or more further variable impedance elements.