Adjacent Channel Interference Cancellation in Multi-Channel Systems

• US 20150131493A1
• Filed: 11/14/2014
• Published: 05/14/2015
• Est. Priority Date: 11/14/2013
• Status: Active Grant

• Current Assignee: Parallel Wireless, Inc.
• Original Assignee: Parallel Wireless, Inc.
• Inventors: Navalekar, Abhijit, Mishra, Rajesh Kumar, Garg, Sumit
• Granted Patent: US 10,044,490 B2
• Time in Patent Office: Days
• US Class Current: 370/278
• CPC Class Codes: H04L 5/14 Two-way operation using the same type of signal, i.e. duplex

Abstract

A method for adjacent channel interference cancellation may be disclosed, comprising collecting adjacent channel usage samples at a first time; assigning coefficient weights in an adjacent channel interference model based on the adjacent channel usage samples; determining whether a radio may be available for measuring current adjacent channel usage; adjusting coefficient weights based on the current adjacent channel usage; and canceling noise in an adjacent channel at a second time based on the coefficient weights. A radio frequency chain may be coupled to the output of the radio transceiver and configured to sample adjacent channel interference caused by the radio transceiver.

Claims

1. A method for adjacent channel interference cancellation, comprising:

collecting adjacent channel usage samples at a first time;

assigning coefficient weights in an adjacent channel interference model based on the adjacent channel usage samples;

determining whether a radio is available for measuring current adjacent channel usage;

adjusting coefficient weights based on the current adjacent channel usage; and

canceling noise in an adjacent channel at a second time based on the coefficient weights.

2. The method of claim 1, wherein canceling noise is performed in the digital domain and in the analog domain.

3. The method of claim 1, wherein the first time is more than 5 milliseconds prior to the second time.

4. The method of claim 1, further comprising determining whether the radio is available for measuring current adjacent channel usage based on an unused time slot in a time division duplexing scheme.

5. A radio transceiver system, comprising:

a memory configured to store instructions;

a radio transceiver, the radio transceiver being configurable for receiving radio transmissions on a plurality of frequencies and to obtain a sample of an adjacent channel interference signal; and

a processor coupled to the memory, the radio transceiver and the radio frequency chain configured to compute an adjacent channel interference cancellation signal based on the adjacent channel interference signal sample.

6. The radio transceiver system of claim 5, further comprising a radio frequency chain coupled to the output of the radio transceiver and configured to sample adjacent channel interference caused by the radio transceiver.

7. The radio transceiver system of claim 6, wherein the radio frequency chain is configured to perform noise cancellation in the analog domain.

8. The radio transceiver system of claim 5, further comprising a storage module for storing adjacent channel samples, and the processor further configured to precompute a plurality of coefficients for multiplying the adjacent channel interference cancellation signal based on the stored adjacent channel samples.

9. The radio transceiver system of claim 5, wherein the radio transceiver is a software-defined radio.

10. The radio transceiver system of claim 5, further comprising a second radio transceiver.

11. A system for canceling adjacent channel interference, comprising:

a multi-radio access technology (RAT) base station, the base station further comprising;

a memory configured to store instructions,

a radio transceiver, the radio transceiver being configurable for receiving radio transmissions on a plurality of frequencies and to obtain a sample of an adjacent channel interference signal, and

a processor coupled to the memory, the radio transceiver and the radio frequency chain configured to compute an adjacent channel interference cancellation signal based on the sample of the adjacent channel interference signal; and

a coordination server, the coordination server further comprising;

an interference cancellation module configured to receive the sample of the adjacent channel interference signal, and configured to determine coefficient weights in an adjacent channel interference signal.

12. The system of claim 11, wherein the interference cancellation module is configured to use a neural network to determine the coefficient weights.

13. The system of claim 11, wherein the interference cancellation module is configured to use samples from more than one multi-RAT base station to determine coefficient weights.

14. The system of claim 11, wherein the multi-RAT base station is configured to receive the determined coefficient weights from the coordination server and is configured to apply an adjacent channel interference cancellation signal based on the determined coefficient weights.