Method and apparatus for mitigating interference in a wireless network through use of transmit beamforming

1. A method for reducing interference in wireless communications, the method comprising:

at least one of

i) determining, at a first communication device, a beamforming matrix based on an estimate of a multiple input, multiple output (MIMO) communication channel between the first communication device and a second communication device, wherein the first communication device and the second communication device belong to a first wireless network, wherein the beamforming matrix is determined without using channel estimate information corresponding to a communication channel to any third communication device in a second wireless network, and wherein the second wireless network omits the first communication device, or

ii) receiving, at the first communication device, the beamforming matrix, the beamforming matrix having been generated a) based on the estimate of the MIMO communication channel and b) without using channel estimate information corresponding to the communication channel to any third communication device in the second wireless network;

the method further comprising:

determining, at the first communication device, at least one of i) whether a distance between the first communication device and one of the third communication devices is less than a distance threshold and ii) whether transmissions from the second wireless network meet a signal strength criteria;

in response to determining at least one of i) that the distance is less than a distance threshold and ii) that the transmissions from the second wireless network meet the signal strength criteria, determining that the first communication device is near to the second wireless network and that transmissions from the first communication device in the first wireless network are producing interference to the second wireless network;

determining, at the first communication device, whether the first communication device receives from any third communication device in the second wireless network via a communication link a request for the first communication device to reduce interference to the second wireless network, wherein the request is in response to the produced interference to the second wireless network;

in response to determining that transmissions from the first communication device in the first wireless network are producing interference to the second wireless network, reducing, by using the beamforming matrix at the first communication device, the interference to the second wireless network, wherein the interference is generated by the first communication device transmitting to the second communication device via the MIMO communication channel;

coordinating, at the first communication device, with an access point in the second wireless network so that the first communication device uses a first beamforming matrix for a first downlink transmission when the access point is scheduled to perform a second downlink transmission to a client communication device in the second wireless network; and

coordinating, at the first communication device, with the access point in the second wireless network so that the first communication device schedules one or more first uplink transmissions in the first wireless network at times different than when the access point schedules one or more second uplink transmissions in the second wireless network;

wherein

the one or more first uplink transmissions are one or more transmissions from the second communication device to the first communication device, and

the one or more second uplink transmissions are one or more transmissions from the fourth communication device or from one or more other client communication devices in the second wireless network to the access point.

2. The method of claim 1 , further comprising determining, at the first communication device, the estimate of the MIMO communication channel.

3. The method of claim 1 , wherein determining the estimate of the MIMO communication channel includes receiving the estimate of the MIMO communication channel from the second communication device.

4. The method of claim 1 , wherein the MIMO communication channel is below 6 GHz.

5. The method of claim 4 , wherein the MIMO communication channel is above 2 GHz.

6. The method of claim 1 , wherein the second wireless network omits the second communication device.

7. An apparatus corresponding to a first communication device, the apparatus comprising:

a network interface including

i) a media access control (MAC) processing unit, and

ii) a physical layer (PHY) processing unit coupled to the MAC processing unit;

wherein the PHY processing unit is configured to at least one of

i) determine a beamforming matrix based on an estimate of a multiple input, multiple output (MIMO) communication channel between the first communication device and a second communication device, wherein the first communication device and the second communication device belong to a first wireless network, wherein the beamforming matrix is determined without using channel estimate information corresponding to a communication channel to any third communication device in a second wireless network, and wherein the second wireless network omits the first communication device, or

ii) receive the beamforming matrix, the beamforming matrix having been generated a) based on the estimate of the MIMO communication channel and b) without using channel estimate information corresponding to the communication channel to any third communication device in the second wireless network; and

wherein the network interface is configured to

determine at least one of i) whether a distance between the first communication device and one of the third communication devices is less than a distance threshold and ii) whether transmissions from the second wireless network meet a signal strength criteria,

in response to a determination of at least one of i) that the distance is less than a distance threshold and ii) that the transmissions from the second wireless network meet the signal strength criteria, determine that the first communication device is near to the second wireless network and that transmissions from the first communication device in the first wireless network are producing interference to the second wireless network,

determine whether the first communication device receives from any third communication device in the second wireless network via a communication link a request for the first communication device to reduce interference to the second wireless network,

in response to a determination that the request for the first communication device to reduce interference to the second wireless network is received, determine that transmissions from the first communication device in the first wireless network are producing interference to the second wireless network,

in response to a determination that transmissions from the first communication device in the first wireless network are producing interference to the second wireless network, reduce, by use of the beamforming matrix, the interference to the second wireless network, wherein the interference is generated by the first communication device transmitting to the second communication device,

use the beamforming matrix for the purpose of reducing interference to the second wireless network caused by the first communication device transmitting to the second communication device via the MIMO communication channel,

coordinate with an access point in the second wireless network so that the first communication device uses a first beamforming matrix for a first downlink transmission when the access point is scheduled to perform a second downlink transmission to a client communication device in the second wireless network, and

coordinate with the access point in the second wireless network so that the first communication device schedules one or more first uplink transmissions in the first wireless network at times different than when the access point schedules one or more second uplink transmissions in the second wireless network;

wherein

the one or more first uplink transmissions are one or more transmissions from the second communication device to the first communication device and

the one or more second uplink transmissions are one or more transmissions from the fourth communication device or from one or more other client communication devices in the second wireless network to the access point.

8. The apparatus of claim 7 , wherein the PHY processing unit is configured to determine the estimate of the MIMO communication channel.

9. The apparatus of claim 7 , wherein the PHY processing unit is configured to determine the estimate of the MIMO communication channel based on receiving the estimate of the MIMO communication channel from the second communication device.

10. The apparatus of claim 7 , wherein the MIMO communication channel is below 6 GHz.

11. The apparatus of claim 10 , wherein the MIMO communication channel is above 2 GHz.

12. The apparatus of claim 7 , wherein the second wireless network omits the second communication device.

13. A method for reducing interference in wireless communications, the method comprising:

selecting, at a first access point (AP) of a first wireless network, a beamforming matrix, wherein

the first AP belongs to a first wireless network, and

the first AP communicates with one or more first client communication devices in the first wireless network via a communication channel below 6 GHz,

the first AP is communicatively coupled, via a communication link separate from the first wireless network and a second wireless network, to a second AP of the second wireless network;

determining, by the first AP, at least one of i) whether a distance between the first AP and the second AP is less than a distance threshold and ii) whether transmissions from the second wireless network meet a signal strength criteria; and

in response to determining at least one of i) that the distance is less than a distance threshold and ii) that the transmissions from the second wireless network meet the signal strength criteria, determining that the second AP is near to the first AP and that transmissions from the first AP in the first wireless network are producing interference to the second wireless network;

determining, by the first AP, whether the first AP receives from the second AP or from a second client communication device in the second wireless network via the communication link and in response to the produced interference to the second wireless network, a request for the first AP to reduce interference to the second wireless network;

in response to determining that the request for the first AP to reduce interference to the second wireless network is received, determining that transmissions from the first AP in the first wireless network are producing interference to the second wireless network;

in response to determining that transmissions from the first AP in the first wireless network are producing interference to the second wireless network, reducing, by using the beamforming matrix at the first AP, the interference to the second wireless network, wherein the interference is generated by downlink transmissions from the first AP to the one or more first client communication devices;

coordinating, at the first AP, with the second AP so that the first AP uses a first beamforming matrix for a first downlink transmission when the second AP is scheduled to perform a second downlink transmission to the second client communication device in the second wireless network; and

coordinating, at the first AP, with the second AP so that the first AP schedules one or more first uplink transmissions in the first wireless network at times different than when the second AP schedules one or more second uplink transmissions in the second wireless network,

wherein

the second wireless network omits the first AP,

the one or more first uplink transmissions are one or more transmissions from the one or more first communication client devices to the first AP, and

the one or more second uplink transmissions are one or more transmissions from the second client communication device or from one or more other second client communication devices in the second wireless network to the second AP.

14. The method of claim 13 , wherein:

selecting the beamforming matrix comprises selecting from a plurality of pre-generated beamforming matrices in coordination with the second AP.

15. The method of claim 13 , wherein using the beamforming matrix comprises using the beamforming matrix to transmit a broadcast packet from the first AP to multiple first client communications devices.

16. The method of claim 13 , wherein selecting the beamforming matrix comprises selecting, at the first AP, the beamforming matrix from a plurality of pre-generated beamforming matrices.

17. The method of claim 16 , wherein:

the beamforming matrix is a first beamforming matrix from the plurality of pre-generated beamforming matrices;

using the first beamforming matrix comprises using the first beamforming matrix at a first time; and

the method further comprises:

selecting, at the first AP, a second beamforming matrix from the plurality of pre-generated beamforming matrices, and

using the second beamforming matrix at the first AP at a second time for the purpose of reducing interference to the second wireless network caused by the first AP transmitting to the one or more first client communication devices via the communication channel.

18. The method of claim 17 , wherein:

using the first beamforming matrix at the first time comprises using the first beamforming matrix to transmit a broadcast packet from the first AP; and

using the second beamforming matrix at the second time comprises using the second beamforming matrix to re-transmit the broadcast packet from the first AP.

19. The method of claim 13 , wherein the communication channel is above 2 GHz.

20. An apparatus corresponding to a first access point (AP), the apparatus comprising:

a network interface including

i) a media access control (MAC) processing unit, and

ii) a physical layer (PHY) processing unit coupled to the MAC processing unit;

wherein

the first AP belongs to a first wireless network,

the first AP communicates with one or more first client communication devices in the first wireless network via a communication channel below 6 GHz,

the network interface is configured to

select a beamforming matrix, and

use the beamforming matrix at the first AP for the purpose of reducing interference to a second wireless network caused by the first AP transmitting to the one or more first client communication devices via the communication channel,

and wherein

the network interface is communicatively coupled, via a communication link separate from the first wireless network and the second wireless network, to a second AP of the second wireless network,

the network interface is configured to determine at least one of i) whether a distance between the first AP and the second AP is less than a distance threshold and ii) whether transmissions from the second wireless network meet a signal strength criteria,

in response to a determination of at least one of i) that the distance is less than a distance threshold and ii) that the transmissions from the second wireless network meet the signal strength criteria, determine that the second AP is near to the first AP and that transmissions from the first AP in the first wireless network are producing interference to the second wireless network,

the network interface is configured to determine whether the first AP receives from the second AP or from a second client communication device in the second wireless network via the communication link and in response to the produced interference to the second wireless network, a request for the first AP to reduce interference to the second wireless network,

in response to a determination that the request for the first AP to reduce interference to the second wireless network is received, determine that transmissions from the first AP in the first wireless network are producing interference to the second wireless network,

the network interface is configured to, in response to a determination that transmissions from the first AP in the first wireless network are producing interference to the second wireless network, reduce, by use of the beamforming matrix at the first AP, the interference to the second wireless network, wherein the interference is generated by downlink transmissions from the first AP to the one or more first client communication devices,

the network interface is configured to coordinate with the second AP so that the first AP uses the beamforming matrix for a first downlink transmission when the second AP is scheduled to perform a second downlink transmission to a second client communication device in the second wireless network, and

the network interface is configured to coordinate with the second AP so that the first AP schedules one or more first uplink transmissions in the first wireless network at times different than when the second AP schedules one or more second uplink transmissions in the second wireless network, and

the second wireless network omits the first AP,

the one or more first uplink transmissions are one or more transmissions from the one or more first client communication devices to the first AP, and

the one or more second uplink transmissions are one or more transmissions from the second client communication device or from one or more other second client communication devices in the second wireless network to ii) the second AP.

21. The apparatus of claim 20 , wherein:

the network interface is configured to select the beamforming matrix from a plurality of pre-generated beamforming matrices in coordination with the second AP.

22. The apparatus of claim 20 , wherein the network interface is configured to use the beamforming matrix to transmit a broadcast packet from the first AP to multiple first client communications devices.

23. The apparatus of claim 22 , wherein the network interface is configured to:

use a first beamforming matrix at a first time to transmit a broadcast packet from the first AP, and

use a second beamforming matrix at a second time to re-transmit the broadcast packet from the first AP.

24. The apparatus of claim 20 , wherein the network interface is configured to select the beamforming matrix from a plurality of pre-generated beamforming matrices.

25. The apparatus of claim 24 , wherein:

the beamforming matrix is a first beamforming matrix from the plurality of pre-generated beamforming matrices;

the network interface is configured to:

use the first beamforming matrix at a first time,

select a second beamforming matrix from the plurality of pre-generated beamforming matrices, and

use the second beamforming matrix at the first AP at a second time for the purpose of reducing interference to the second wireless network caused by the first AP transmitting to the one or more first client communications device via the communication channel.

26. The apparatus of claim 20 , wherein the communication channel is above 2 GHz.

27. A system, comprising:

a first access point (AP) of a first wireless network;

a second AP of a second wireless network that omits the first AP, wherein the first AP is communicatively coupled, via a communication link separate from the first wireless network and the second wireless network, to the second AP;

wherein

the first AP comprises a network interface including

i) a media access control (MAC) processing unit, and

ii) a physical layer (PHY) processing unit coupled to the MAC processing unit;

the first AP communicates with one or more first client communication devices in the first wireless network via a communication channel below 6 GHz,

the network interface is configured to

determine at least one of i) whether a distance between the first AP and the second AP is less than a distance threshold and ii) whether transmissions from the second wireless network meet a signal strength criteria,

in response to determining at least one of i) that the distance is less than a distance threshold and ii) that the transmissions from the second wireless network meet the signal strength criteria, determining that the second AP is near to the first AP and that transmissions from the first AP in the first wireless network are producing interference to the second wireless network,

determine whether the first AP receives from the second AP or from a second client communication device in the second wireless network via the communication link and in response to the produced interference to the second wireless network, a request for the first AP to reduce interference to the second wireless network,

in response to determining that the request for the first AP to reduce interference to the second wireless network is received, determining that transmissions from the first AP in the first wireless network are producing interference to the second wireless network,

select a beamforming matrix,

in response to a determination that transmissions from the first AP in the first wireless network are producing interference to the second wireless network, reduce, by using the beamforming matrix at the first AP, the interference to the second wireless network, wherein the interference is generated by downlink transmissions from the first AP to the one or more first client communication devices,

coordinate with the second AP so that the first AP uses the beamforming matrix for a first downlink transmission when the second AP is scheduled to perform a second downlink transmission to a second client communication device in the second wireless network, and

coordinate with the second AP so that the first AP schedules one or more first uplink transmissions in the first wireless network at times different than when the second AP schedules one or more second uplink transmissions in the second wireless network;

wherein,

the one or more first uplink transmissions are one or more transmissions from the one or more first client communication devices to the first AP, and

the one or more second uplink transmissions are one or more transmissions from the second client communication device or from one or more other second client communication devices in the second wireless network to the second AP.

28. The system of claim 27 , further comprising:

a third communication device that communicatively couples the first AP to the second AP of the second wireless network.

29. The system of claim 28 , wherein the third communication device is configured to:

coordinate the first AP and the second AP so that the network interface uses the beamforming matrix for the first downlink transmission when the second AP is scheduled to perform the second downlink transmission;

cause the first AP to schedule one or more first uplink transmissions in the first wireless network at times different than when the second AP schedules one or more second uplink transmissions in the second wireless network.