Multi-channel RF system with off-channel scanning

1. A radio communication system comprising:

a plurality of transceivers configured to communicate in a plurality of radio communication channels, a first subset of the plurality of radio communication channels being used by the first subset of the plurality of transceivers for performing radiofrequency communication functions, and a second subset of the plurality of channels being used for performing off-channel functions; and

circuitry configured to perform the off-channel functions concurrently with communication functions being performed in the first subset of the plurality of channels, the off-channel functions including scanning unused channels among the first subset of the plurality of channels for interference, to determine availability of channels among the unused channels for performing radiofrequency communication functions, the circuitry configured to perform the off-channel functions including memory configured to store identifications of channels determined to be interference-free, and being further configured to, upon detection of interference on a channel in the first subset of the plurality of channels that is being used for performing radiofrequency communication functions, select one of the interference-free channels whose identification is stored, for use in place of the channel on which interference is detected; wherein:

the system operates under a protocol providing for first channels having a base bandwidth and second channels comprising two of the first channels and having a second bandwidth that is twice the base bandwidth; and

the second subset of the plurality of channels comprises one of the first channels, having the base bandwidth, that is included in one of the second channels having the second bandwidth.

2. The radio communication system of claim 1 wherein another of the first channels, having the base bandwidth, that is included in the one of the second channels having the second bandwidth, performs the radiofrequency communications functions, such that half of the one of the second channels is used for the radiofrequency communications functions and half of the one of the second channels is used for the off-channel functions.

3. The radio communication system of claim 1 wherein the circuitry configured to perform the off-channel functions uses the second subset of the plurality of channels to operate under a neighborhood discovery protocol that analyzes a surrounding radiofrequency environment.

4. The radio communication system of claim 1 wherein:

the first subset of the plurality of transceivers performs communication functions in the first subset of the plurality of radio communication channels on selected frequencies; and

the circuitry configured to perform the off-channel functions uses the second subset of the plurality of channels to scan for microwave interference on the selected frequencies.

5. The radio communication system of claim 4 wherein the microwave interference is radar interference.

6. The radio communication system of claim 5 wherein the circuitry configured to perform the off-channel functions comprises circuitry configured to perform dynamic frequency selection to remove radiofrequency communication functions from radar channels.

7. The radio communication system of claim 1 wherein the second subset of the plurality of channels includes only one channel.

8. The radio communication system of claim 1 wherein:

the first subset of the plurality of transceivers performs communication functions in the first subset of the plurality of radio communication channels on selected frequencies; and

the circuitry configured to perform the off-channel functions uses the second subset of the plurality of channels to scan for microwave interference on the selected frequencies.

9. The radio communication system of claim 1 wherein:

the first subset of the plurality of transceivers is configured to provide the first subset of the plurality of channels; and

a second subset of the plurality of transceivers is configured to provide the second subset of the plurality of channels.

10. The radio communication system of claim 9 further comprising a spectrum sensing unit for selecting between the first subset of the plurality of transceivers that performs radiofrequency communication functions and the second subset of the plurality of transceivers that provides signals for the off-channel functions.

11. A method of operating a radio communication system including a plurality of transceivers configured to communicate in a plurality of radio communication channels and circuitry configured to perform off-channel functions, the method comprising:

using a first subset of the plurality of channels to perform radiofrequency communication functions, including operating the first subset of the plurality of channels under a protocol providing for first channels having a base bandwidth and second channels comprising two of the first channels and having a second bandwidth that is twice the base bandwidth; and

using a second subset of the plurality of channels, including one of the first channels, having the base bandwidth, that is included in one of the second channels having the second bandwidth to perform the off-channel functions, including using the second subset of the plurality of channels to scan available communications channels for interference.

12. The method of claim 11 comprising using another of the first channels, having the base bandwidth, that is included in the one of the second channels having the second bandwidth, to perform the radiofrequency communications functions, such that half of the one of the second channels is used for the radiofrequency communications functions and half of the one of the second channels is used for the off-channel functions.

13. The method of claim 12 wherein the using a second subset of the plurality of channels to perform the off-channel functions comprises using the second subset of the plurality of channels to operate under a neighborhood discovery protocol that analyzes a surrounding radiofrequency environment.

14. The method of claim 11 wherein:

the using the first subset of the plurality of radio communication channels comprises operating the first subset of the plurality of transceivers on selected frequencies; and

the using the second subset of the plurality of channels to perform the off-channel functions comprises using the second subset of the plurality of channels to scan for microwave interference on the selected frequencies.

15. The method of claim 14 wherein the microwave interference is radar interference.

16. The method of claim 15 wherein the off-channel functions comprise dynamic frequency selection to remove radiofrequency communication functions from radar channels.

17. The method of claim 11 further comprising: storing identifications of channels determined to be interference-free; and

upon detection of interference on a channel among the first subset of the plurality of channels being used for performing radiofrequency communication functions, selecting one of the interference-free channels whose identification is stored, for use in place of the channel on which interference is detected.