RF domains

Abstract

A wireless access point broadcasts a unique rf domain identifier for each supported service set per radio. Within a wireless local area network (“WLAN”) the rf domain identifier is unique for each supported service set, and hence identifies the service set. In addition to identifying the service sets supported by the access point, rf domain identifiers may be used to adjust transmit power in order to differentiate service sets. For example, if a first access point receives a beacon with an rf domain identifier transmitted by a second access point, the transmit power of communications associated with the service set associated with the received rf domain identifier is reduced at the first access point if that service set is also supported on the same radio by the first access point. In one embodiment the first and second access points both reduce transmit power until the beacons are no longer received by the respective nearby access point. The transmit power of communications associated with other service sets and other radios are not effected by the transmit power reduction, i.e., the access point may reduce transmit power of overlapping service set communications while contemporaneously transmitting communications of non-overlapping service sets at full power.

Description

(published as U.S. Patent Application Publication No. 2005/0026611), which is incorporated herein by reference. Initially, access point (100) transmits at maximum power. Once access point (100) has successfully claimed the channel it determines whether another access point is operating on the same channel as indicated by step (300). If another access point is operating on the channel, e.g., access point (102), a determination is made whether there is an intersection between the service set it is supporting and the service set advertised by the beacons it receives as indicated in step (302). If the nearby access point (102) is broadcasting a beacon (116) advertising an intersecting service set, e.g., RF domain identifier A on the same radio, then access point (100) calculates a transmit power (“TP”) backoff value and adjusts its transmit power for data transmissions associated with that service set downward to facilitate overall RF domain identifier A service set throughput in the WLAN as indicated in step (304). The power adjustment routine is contemporaneously adjusted by both access points (100, 102), provided both access points receive the beacons from one-another, until transmission power is decreased to a point at which the beacons are no longer received. The access points may maintain tables which identify nearby access points and variables such as a Max TP backoff value to facilitate power adjustment.

The power adjustment routine may also be triggered based on service set priority. For example, if access point (102) receives a beacon (120) from access point (104), the beacon (120) is examined to determine the service set that is being advertised, e.g., RF domain identifier C. Access point (102) then determines from a table maintained in memory whether any of the service sets supported by access point (102) on the same channel with the same radio have a lower priority than RF domain identifier C. The transmit power of each lower priority service set is reduced to a level calculated to not reach access point (120). The calculation may be facilitated by including an indicator of transmit power level in beacon (120). The difference between the indicated transmit power level in the beacon (120) and the actual power level of the beacon as received at access point (102) provides an indication of the transmit power level at which communications will reach access point (104).

While the invention is described through the above exemplary embodiments, it will be understood by those of ordinary skill in the art that modification to and variation of the illustrated embodiments may be made without departing from the inventive concepts herein disclosed. Moreover, while the preferred embodiments are described in connection with various illustrative structures, one skilled in the art will recognize that the system may be embodied using a variety of specific structures. Accordingly, the invention should not be viewed as limited except by the scope and spirit of the appended claims.

Claims

1. Apparatus for providing radio frequency (“RF”) access in support of at least one service to a client device, comprising:

a receiver operable to receive communications from the client device and to receive an rf domain identifier transmitted by another device;

processing logic operable to determine whether the service associated with the received rf domain identifier has a higher priority than supported services, and to reduce transmit power of communications associated with supported services having lower priority than the service associated with the received rf domain identifier; and

a transmitter operable to transmit communications to the client device, the transmitter being further operable to support multiple services, and to transmit an rf domain identifier associated with each supported service,

wherein the supported service includes at least one of:

all service types provided by a communications service provider;

a subset of service types provided by the service provider;

a particular service type associated with a service provider; and

at least one service type provided by multiple communications service providers; and

wherein the service types include at least one of voice, video, data, Internet access, and local area network (“LAN”) access to applications.

2. The apparatus of claim 1 wherein the transmitter is further operable to transmit a unique rf domain identifier for each supported service per radio.

3. The apparatus of claim 1 wherein the rf domain identifier is included in a beacon.

4. The apparatus of claim 1 further including processing logic operable to reduce transmit power of communications associated with a service following detection of overlapping support for the service by the other device.

5. The apparatus of claim 4 wherein communications associated with two different services are transmitted at different power levels.

6. The apparatus of claim 1 further including processing logic operable to transmit communications associated with a supported service having lower priority at a relatively lower power than a service having a relatively higher priority.

7. A method for providing radio frequency (“RF”) access in support of at least one service to a client device, comprising: receiving communications from the client device; transmitting communications to the client device; supporting multiple services by broadcasting an rf domain identifier associated with each supported service, wherein the supported service includes at least one of:

all service types provided by a communications service provider;

a subset of service types provided by the service provider;

a particular service type associated with a service provider; and

at least one service type provided by multiple communications service providers; and wherein the service types include at least one of voice, video, data, Internet access, and local area network (“LAN”) access to applications; and receiving an rf domain identifier transmitted by another device; and determining whether the service associated with the received rf domain identifier has a higher priority than supported services; and reducing transmit power of communications associated with supported services having lower priority than the service associated with the received rf domain identifier.

8. The method of claim 7 further including the step of broadcasting a unique rf domain identifier per radio for each supported service.

9. The method of claim 7 wherein the rf domain identifier is included in a beacon.

10. The method of claim 7 further including the step of reducing transmit power of communications associated with the service associated with the received rf domain identifier, provided that service is supported via the same radio, i.e., service support overlaps.

11. The method of claim 10 further including the step of transmitting at different power levels communications associated with two different services.

12. The method of claim 7 further including the step of reducing transmit power of communications associated with supported services having lower priority than the service associated with the received rf domain identifier.

13. The method of claim 7 wherein transmit power of communications associated with supported services having equal or higher priority than the service associated with the received rf domain identifier are not reduced.

14. A wireless access point comprising:

a transmitter configured to transmit a signal containing an identification of at least one service offered by the wireless access point; and

a receiver configured to receive from at least one other wireless access point at least one signal containing an identification of at least one service offered by the at least one other wireless access point;

wherein the wireless access point is configured:

to determine whether a received identification of at least one service offered by the at least one other wireless access point identifies at least one service also offered by the wireless access point, and,

to reduce a power level to be used by the transmitter to transmit at least signals associated with the at least one service also offered by the wireless access point, in the case where it is determined that the received identification of at least one service offered by the at least one other wireless access point identifies at least one service also offered by the wireless access point.

15. The wireless access point of claim 14, wherein the transmitter is configured to transmit a beacon containing the identification of at least one service offered by the wireless access point.

16. The wireless access point of claim 14, wherein the identification of at least one service offered by the wireless access point comprises a name of a service provider offering the at least one service.

17. The wireless access point of claim 14, wherein the wireless access point in configured to reduce the power level to be used by the transmitter to transmit at least signals associated with the at least one service also offered by the wireless access point by calculating a transmit power backoff value.

18. The wireless access point of claim 14, wherein the transmitter includes multiple radio transmitters supporting multiple communication channels.

19. The wireless access point of claim 18, wherein the wireless access point is configured to reduce a power level to be used by the transmitter to transmit at least signals associated with the at least one service also offered by the wireless access point by calculating a transmit power level such that a beacon being transmitted for the service will not be received by the at least one other wireless access point.

20. The wireless access point of claim 19, wherein the calculating includes computing a difference between a received power level and an indicated transmit power level of the at least one signal received from the at least one other wireless access point.

21. A method of wireless communication, comprising:

transmitting, by a wireless access point, a signal containing an identification of at least one service offered by the wireless access point;

receiving, at the wireless access point, at least one signal from at least one other wireless access point, wherein the at least one signal contains an identification of at least one service offered by the at least one other wireless access point;

determining whether at least one receive identification of at least one service offered by the at least one other wireless access point identifies at least one service also offered by the wireless access point; and

reducing a transmit power level to be used for transmitting at least signals associated with the at least one service also offered by the wireless access point, in the case where the at least one receive identification of at least one service offered by the at least one other wireless access point identifies at least one service also offered by the wireless access point.

22. The method of claim 21, wherein said transmitting includes transmitting a beacon containing the identification of at least one service offered by the wireless access point.

23. The method of claim 21, wherein the identification of at least one service offered by the wireless access point comprises a name of a service provider offering the at least one service.

24. The method of claim 21, wherein said reducing the transmit power to be used for transmitting at least signals associated with the at least one service also offered by the wireless access point includes calculating a transmit power backoff value.

25. The method of claim 21, wherein said reducing the transmit power to be used for transmitting at least signals associated with the at least one service also offered by the wireless access point comprises calculating a transmit power level such that a beacon being transmitted for the service will not be received by the at least one other wireless access point.

26. The method of claim 25, wherein the calculating includes computing a difference between a received power level and an indicated transmit power level of the at least one signal received from the at least one other wireless access point.

27. A non-transitory computer-readable storage medium containing instructions for execution by a processing apparatus of a wireless access point, wherein the instructions are configured to result in the implementation of operations comprising:

transmitting a signal containing an identification of at least one service offered by the wireless access point;

receiving at least one signal from at least one other wireless access point, wherein the at least one signal contains an identification of at least one service offered by the at least one other wireless access point;

determining whether at least one receive identification of at least one service offered by the at least one other wireless access point identifies at least one service also offered by the wireless access point; and

reducing a transmit power level to be used for transmitting at least signals associated with the at least one service also offered by the wireless access point, in the case where the at least one receive identification of at least one service offered by the at least one other wireless access point identifies at least one service also offered by the wireless access point.

28. The medium of claim 27, wherein said transmitting includes transmitting a beacon containing the identification of at least one service offered by the wireless access point.

29. The medium of claim 27, wherein the identification of at least one service offered by the wireless access point comprises a name of a service provider offering the at least one service.

30. The medium of claim 27, wherein said reducing the transmit power to be used for transmitting at least signals associated with the at least one service also offered by the wireless access point includes calculating a transmit power backoff value.

31. The medium of claim 27, wherein said reducing the transmit power to be used for transmitting at least signals associated with the at least one service also offered by the wireless access point comprises calculating a transmit power level such that a beacon being transmitted for the service will not be received by the at least one other wireless access point.

32. The medium of claim 31, wherein the calculating includes computing a difference between a received power level and an indicated transmit power level of the at least one signal received from the at least one other wireless access point.