Radio transceiver with improved radar detection

• US 8,982,772 B2
• Filed: 01/09/2014
• Issued: 03/17/2015
• Est. Priority Date: 08/17/2011
• Status: Active Grant

• Current Assignee: COMS IP Holdings LLC
• Original Assignee: CBF Networks, Inc. (COMSovereign Holding Corp.)
• Inventors: Fischer, Jeffrey, Gandham, Kishore, Negus, Kevin J.
• Primary Examiner(s): Phillips, Hassan
• Assistant Examiner(s): Sharma, Gautam
• Application Number:
  US14/151,190
• Publication Number:
  US 20140120966A1
• Time in Patent Office: 432 Days
• Field of Search: None
• US Class Current: 370/315
• CPC Class Codes: H01Q 1/246 specially adapted for base stations
• CPC Class Codes: H01Q 21/24 Combinations of antenna units polarised in different directions for transmitting or receiving circularly and elliptically polarised waves or waves linearly polarised in any direction circularly polarised patch antennas H01Q9/0428; circularly polarised horns H01Q13/0241; cross-polarised horns H01Q13/0258; polarisation converters H01Q15/242; cross-polarised rear feeds H01Q19/136; crossed polarisation dual antenna H01Q25/001
• CPC Class Codes: H01Q 21/29 Combinations of different interacting antenna units for giving a desired directional characteristic H01Q25/00 takes precedence
• CPC Class Codes: H01Q 25/00 Antennas or antenna systems providing at least two radiating patterns arrangements for changing or varying the orientation or the shape of the directional pattern H01Q3/00
• CPC Class Codes: H01Q 25/005 providing two patterns of opposite direction; back to back antennas H01Q25/004 takes precedence
• CPC Class Codes: H04B 7/04 using two or more spaced independent antennas
• CPC Class Codes: H04K 2203/32 including a particular configuration of antennas
• CPC Class Codes: H04K 2203/36 including means for exchanging jamming data between transmitter and receiver, e.g. in forward or backward direction
• CPC Class Codes: H04K 3/224 with countermeasures at transmission and/or reception of the jammed signal, e.g. stopping operation of transmitter or receiver, nulling or enhancing transmitted power in direction of or at frequency of jammer
• CPC Class Codes: H04K 3/226 Selection of non-jammed channel for communication spectrum sharing arrangements H04W16/14; selection of wireless resources by user or terminal H04W72/02
• CPC Class Codes: H04K 3/28 with jamming and anti-jamming mechanisms both included in a same device or system, e.g. wherein anti-jamming includes prevention of undesired self-jamming resulting from jamming
• CPC Class Codes: H04K 3/822 by detecting the presence of a surveillance, interception or detection
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 52/367 Power values between minimum and maximum limits, e.g. dynamic range
• CPC Class Codes: H04W 72/541 using the level of interference

Abstract

A radar detector is used with a radio link, the radio link characterized by high duty factor operation of a radio transmitter. The radar detector is located a sufficient distance from the radio transmitter that the radar detector is not overwhelmed by the radio transmission signal in that channel and can detect sufficiently low level radar signals to ascertain potential radio interference at the radar from said radio transmitter. The results of the radar detection are communicated to the transmitter in a way that impacts the transmitter'"'"'s use of the sensed channel. This communication can occur reactively when a radar detection is achieved (the absence of which indicates no radar has been detected) and/or can be a periodic or event-driven indication that the channel is available for operation (the information expiring if the result is not refreshed).

Claims

1. A wireless communications system comprising:

a first transceiver, wherein the first transceiver comprises a first transmitter, a first receiver, and a first radar detector, and wherein the first transmitter transmits on a first transmit channel;

a second transceiver, wherein the second transceiver comprises a second transmitter and a second receiver, and wherein the second transmitter transmits on a second transmit channel;

wherein the first receiver receives from the second transmitter on the second transmit channel and the second receiver receives from the first transmitter on the first transmit channel;

wherein the first transmit channel is within a first transmit frequency band and the second transmit channel is within a second transmit frequency band;

wherein the first radar detector is configured to detect radars within a first radar detection frequency range that includes at least part of the second transmit frequency band;

wherein the first radar detector is configured to detect radars within at least a first time period, the first time period comprising at least a period of time when the first transmitter and the second transmitter both transmit coincident in time;

wherein the first radar detector communicates at least a first radar detection result via the first transmitter to the second receiver;

wherein the first radar detection result is an input to a controller associated with the second transmitter, and

wherein the first radar detector is configured to be not transmit-impaired by the second transmitter when the second transmitter transmits, at least in part due to a physical separation of the first radar detector and the second transmitter,

wherein the first radar detector is not transmit-impaired by the second transmitter if the first radar detector can still detect radar signals at or above a regulatory limit while the second transmitter is emitting a transmit signal.

2. The wireless communications system of claim 1 wherein the first radar detector is further configured to be not transmit-impaired by the first transmitter when the first transmitter transmits, at least in part due to a physical separation of the first radar detector and the first transmitter.

3. The wireless communications system of claim 1 wherein the first radar detector is further configured to be not transmit-impaired by the first transmitter when the first transmitter transmits, at least in part due to an antenna pattern of the first radar detector relative to the antenna pattern of the first transmitter.

4. The wireless communications system of claim 1 wherein the controller associated with the second transmitter causes the second transmitter to adjust at least one adjustable parameter associated with the second transmit channel.

5. The wireless communications system of claim 4 wherein the at least one adjustable parameter associated with the second transmit channel is a transmit power of the second transmitter.

6. The wireless communications system of claim 4 wherein the at least one adjustable parameter associated with the second transmit channel is a center frequency or a channel bandwidth.

7. The wireless communications system of claim 5 wherein the transmit power of the second transmitter after an adjustment is at a level below that of the regulatory limit for transmit power within a channel for which a radar has been detected.

8. The wireless communications system of claim 1 wherein the first radar detection frequency range includes at least 80% of the bandwidth of the second transmit channel.

9. The wireless communications system of claim 8 wherein the first radar detection frequency range further includes at least 80% of the bandwidth of an alternate channel that is different from the second transmit channel.

10. The wireless communications system of claim 1 wherein the first radar detection result is communicated within a radar detection message, control frame or status that at least indicates whether or not at least one radar has been detected within the first radar detection frequency range.

11. The wireless communications system of claim 1 wherein the first radar detection result is communicated within a radar detection message, control frame or status that at least indicates whether or not at least one radar has been detected within the second transmit channel.

12. The wireless communications system of claim 10 wherein the radar detection message, control frame or status indicates at least one or both of the bandwidth or center frequency of the at least one detected radar within the first radar detection frequency range.

13. The wireless communications system of claim 1 wherein the part of the first time period when at least the first transmitter and the second transmitter both transmit coincident in time is 100% of the first time period for which the first radar detector is configured to at least detect radars.

14. The wireless communications system of claim 4 wherein the controller associated with the second transmitter causes an adjustment of at least one adjustable parameter associated with the second transmit channel depending on the first radar detection result.

15. The wireless communications system of claim 1 wherein the first transmit frequency band overlaps in frequency with the second transmit frequency band.

16. The wireless communications system of claim 1 wherein the first radar detection frequency range does not overlap in frequency with the first transmit frequency band.

17. The wireless communications system of claim 1 wherein the first radar detection frequency range is identical to or a subset of the second transmit frequency band.

18. The wireless communications system of claim 1 further comprising:

a second radar detector;

wherein the second radar detector is configured to detect radars within at least a second time period, the second time period comprising at least a period of time when the first transmitter and the second transmitter both transmit coincident in time;

wherein the second radar detector is configured to detect radars within a second radar detection frequency range.

19. The wireless communications system of claim 18 wherein the first time period overlaps in time with the second time period.

20. The wireless communications system of claim 18 wherein the second radar detection frequency range excludes the second transmit channel.

21. The wireless communications system of claim 18 wherein the second radar detection frequency range includes at least an alternate channel that is different from the second transmit channel.

22. The wireless communications system of claim 18:

wherein the second radar detector is within the first transceiver;

wherein the second radar detector communicates at least a second radar detection result via the first transmitter to the second receiver;

and wherein the second radar detection result is an input to the controller associated with the second transmitter.

23. The wireless communications system of claim 22 wherein the second radar detection result is communicated within a radar detection message, control frame or status that at least indicates whether or not at least one radar has been detected within an alternate channel.

24. The wireless communications system of claim 18:

wherein the second radar detector is within the second transceiver;

wherein the second radar detector communicates at least a second radar detection result via the second transmitter to the first receiver;

and wherein the second radar detection result is an input to a controller associated with the first transmitter.

25. The wireless communications system of claim 18 wherein the second radar detection frequency range is identical to or a subset of the first transmit frequency band.

26. The wireless communications system of claim 23 further comprising:

a third radar detector within the second transceiver;

wherein the third radar detector is configured to detect radars within at least a third time period, the third time period comprising at least a period of time when the first transmitter and the second transmitter both transmit coincident in time;

wherein the third radar detector is configured to detect radars within a third radar detection frequency range;

wherein the third radar detector communicates at least a third radar detection result via the second transmitter to the first receiver;

and wherein the third radar detection result is an input to a controller associated with the first transmitter.

27. The wireless communications system of claim 1 further comprising:

a cancellation circuit within the first transceiver, wherein the cancellation circuit is coupled to at least the first radar detector;

and wherein the cancellation circuit adjusts a signal representative of the output of the first transmitter such that the adjusted signal in combination with a received signal for the first radar detector together result in a reduced level of first transmitter signal impairment to the first radar detector.

28. The wireless communications system of claim 1 further comprising:

a second radio resource controller within the second transceiver, wherein the second radio resource controller comprises the controller associated with the second transmitter;

and wherein the second radio resource controller receives at least one additional link quality input as well as the first radar detection result to adjust at least one parameter associated with the second transmit channel.

29. The wireless communications system of claim 24 further comprising:

a first radio resource controller comprised within the first transceiver, wherein the first radio resource controller comprises the controller associated with the first transmitter;

and wherein the first radio resource controller receives at least one additional link quality input as well as the second radar detection result to adjust at least one parameter associated with the first transmit channel.