Systems and methods for tunable out-of-band interference mitigation

• US 10,236,922 B2
• Filed: 03/27/2018
• Issued: 03/19/2019
• Est. Priority Date: 03/27/2017
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Kumu Networks, Inc.
• Inventors: Choi, Jung-il, Jain, Mayank, Hahn, Wihelm Steffen, Riddle, Alfred
• Primary Examiner(s): Phu, Sanh D
• Application Number:
  US15/937,237
• Publication Number:
  US 20180278280A1
• Time in Patent Office: 357 Days
• Field of Search: 455303
• CPC Class Codes: H04B 1/0057 using diplexing or multiplexing filters for selecting the desired band
• CPC Class Codes: H04B 1/0067 with one or more circuit blocks in common for different bands
• CPC Class Codes: H04B 1/1027 assessing signal quality or detecting noise/interference for the received signal
• CPC Class Codes: H04B 1/50 using different frequencies for the two directions of communication
• CPC Class Codes: H04B 1/525 with means for reducing leakage of transmitter signal into the receiver
• CPC Class Codes: H04B 2001/1045 Adjacent-channel interference

Abstract

A system for interference mitigation includes: a first transmit coupler; a receive-band noise cancellation system; a first transmit-band filter; a second transmit coupler; a first receive coupler; a transmit-band noise cancellation system; a first receive-band filter; and a second receive coupler.

Claims

1. A system for interference mitigation comprising:

a first transmit coupler, communicatively coupled to an analog transmit signal of a communication system, that splits the analog transmit signal into a first-path analog transmit signal and a second-path analog transmit signal;

a receive-band noise cancellation system that samples the first-path analog transmit signal and generates a receive-band noise cancellation signal from the first-path analog transmit signal;

a first transmit-band filter that filters the second-path analog transmit signal in a transmit band, resulting in reduced signal power outside of the transmit band;

a second transmit coupler that combines the receive-band noise cancellation signal and the second-path analog transmit signal, resulting in generation of a reduced-noise analog transmit signal;

wherein the reduced-noise analog transmit signal has further reduced signal power in a receive band relative to the second-path analog transmit signal;

a first receive coupler, communicatively coupled to an analog receive signal of the communication system, that splits the analog receive signal into a first-path analog receive signal and a second-path analog receive signal;

a transmit-band noise cancellation system that samples the first-path analog receive signal and generates a transmit-band noise cancellation signal from the first-path analog receive signal;

a first receive-band filter that filters the second-path analog receive signal in the receive band, resulting in reduced signal power outside of the receive band; and

a second receive coupler that combines the transmit-band noise cancellation signal and the second-path analog receive signal, resulting in generation of a reduced-noise analog receive signal;

wherein the reduced-noise analog receive signal has further reduced signal power in a transmit band relative to the second-path analog receive signal;

wherein the receive-band noise cancellation system delays the receive-band noise cancellation signal by a first amount;

wherein the first transmit-band filter delays the second-path analog transmit signal by a second amount;

wherein the first amount is within ten percent of the second amount.

2. A system for interference mitigation comprising:

a first transmit coupler, communicatively coupled to an analog transmit signal of a communication system, that splits the analog transmit signal into a first-path analog transmit signal and a second-path analog transmit signal;

a receive-band noise cancellation system that samples the first-path analog transmit signal and generates a receive-band noise cancellation signal from the first-path analog transmit signal;

a first transmit-band filter that filters the second-path analog transmit signal in a transmit band, resulting in reduced signal power outside of the transmit band;

a second transmit coupler that combines the receive-band noise cancellation signal and the second-path analog transmit signal, resulting in generation of a reduced-noise analog transmit signal;

wherein the reduced-noise analog transmit signal has further reduced signal power in a receive band relative to the second-path analog transmit signal;

a first receive coupler, communicatively coupled to an analog receive signal of the communication system, that splits the analog receive signal into a first-path analog receive signal and a second-path analog receive signal;

a transmit-band noise cancellation system that samples the first-path analog receive signal and generates a transmit-band noise cancellation signal from the first-path analog receive signal;

a first receive-band filter that filters the second-path analog receive signal in the receive band, resulting in reduced signal power outside of the receive band;

a second receive-band filter that filters the first-path analog transmit signal in the receive band prior to processing by the receive-band noise cancellation system, resulting in further reduced signal power outside of the receive band; and

a second receive coupler that combines the transmit-band noise cancellation signal and the second-path analog receive signal, resulting in generation of a reduced-noise analog receive signal;

wherein the reduced-noise analog receive signal has further reduced signal power in a transmit band relative to the second-path analog receive signal;

wherein the second receive-band filter delays the first-path analog transmit signal by a first amount;

wherein the receive-band noise cancellation system delays the receive-band noise cancellation signal by a second amount;

wherein the first transmit-band filter delays the second-path analog transmit signal by a third amount;

wherein a sum of the first and second amounts is within ten percent of the third amount.

3. The system of claim 2, wherein the receive-band noise cancellation system introduces a first noise component in the transmit band of the receive-band noise cancellation signal;

further comprising a third receive-band filter that filters the receive-band noise cancellation signal, resulting in reduced signal power outside of the receive band and in reduction of the first noise component.

4. The system of claim 3, further comprising a second transmit-band filter that filters the second-path analog transmit signal in the transmit band after filtering by the first transmit-band filter, resulting in further reduced signal power outside of the transmit band.

5. The system of claim 4, further comprising a third transmit-band filter that filters the first-path analog receive signal in the transmit band prior to processing by the transmit-band noise cancellation system, resulting in reduced signal power outside of the transmit band.

6. The system of claim 5, wherein the transmit-band noise cancellation system introduces a second noise component in the receive band of the transmit-band noise cancellation signal;

further comprising a fourth transmit-band filter that filters the transmit-band noise cancellation signal, resulting in reduced signal power outside of the transmit band and in reduction of the second noise component.

7. The system of claim 6, further comprising a fourth receive-band filter that filters the second-path analog receive signal in the receive band after filtering by the first receive-band filter, resulting in further reduced signal power outside of the receive band.

8. A system for interference mitigation comprising:

a first transmit coupler, communicatively coupled to an analog transmit signal of a communication system, that splits the analog transmit signal into a first-path analog transmit signal and a second-path analog transmit signal;

a receive-band noise cancellation system that samples the first-path analog transmit signal and generates a receive-band noise cancellation signal from the first-path analog transmit signal;

a first transmit-band filter that filters the second-path analog transmit signal in a transmit band, resulting in reduced signal power outside of the transmit band;

a second transmit coupler that combines the receive-band noise cancellation signal and the second-path analog transmit signal, resulting in generation of a reduced-noise analog transmit signal;

wherein the reduced-noise analog transmit signal has further reduced signal power in a receive band relative to the second-path analog transmit signal;

a first receive coupler, communicatively coupled to an analog receive signal of the communication system, that splits the analog receive signal into a first-path analog receive signal and a second-path analog receive signal;

a transmit-band noise cancellation system that samples the first-path analog receive signal and generates a transmit-band noise cancellation signal from the first-path analog receive signal;

a first receive-band filter that filters the second-path analog receive signal in the receive band, resulting in reduced signal power outside of the receive band; and

a second receive coupler that combines the transmit-band noise cancellation signal and the second-path analog receive signal, resulting in generation of a reduced-noise analog receive signal;

wherein the reduced-noise analog receive signal has further reduced signal power in a transmit band relative to the second-path analog receive signal;

wherein the transmit-band noise cancellation system delays the transmit-band noise cancellation signal by a first amount;

wherein the first receive-band filter delays the second-path analog receive signal by a second amount;

wherein the first amount is within ten percent of the second amount.

9. The system of claim 8, wherein the transmit-band noise cancellation system introduces a first noise component in the receive band of the transmit-band noise cancellation signal;

further comprising a third transmit-band filter that filters the transmit-band noise cancellation signal, resulting in reduced signal power outside of the transmit band and in reduction of the first noise component.

10. The system of claim 9, further comprising a second receive-band filter that filters the second-path analog receive signal in the receive band after filtering by the first receive-band filter, resulting in further reduced signal power outside of the receive band.