Loading patent…
AssigneeBritish Telecommunications public limited company
InventorsFabrice Saffre, Richard Tateson
Estimating the term…
Wireless devices in (10, 20, 30 etc) in an ad hoc network each select a channel on which to operate such that conflicts with neighbouring devices are avoided. Each device (20) has a normal power output, giving it a normal range (31) and an enhanced power output, giving it an extended “inhibition” range (33). Initially each device (20) transmits at the enhanced power level, such that it can be detected by devices (40, 50) within the extended range (33). If it detects other devices transmitting on the same channel, it may change to another channel. Once a channel has been identified on which no conflict is detected, the device (20) switches to the normal power level. By initiating the channel selection process at the enhanced level, conflicts between the transmissions of devices (20, 40), which would be detectable at a device (30) within the normal range of both, can be avoided despite the two devices (20, 40) not be able to detect each other directly at the normal power level. To conserve battery power, the process is arranged to have the devices operate at the enhanced power for the minimum time necessary, by dropping to the normal level when a suitable channel has been identified with a reasonable degree of certainty.
A wireless communications relay device, comprising a receiver for detecting transmissions from other such devices, and a transmitter for transmitting signals at a first power level for normal traffic, and a higher, inhibition level, in order that its transmissions may be detected by other such devices over a wider area than its normal operating range.
A method of channel selection in a network of wireless communications relay devices, wherein each device is inhibited from operating on a channel detectable on transmissions received from another such device, when operating at an inhibition transmission power, in order to inhibit other such devices from selecting the same channel, wherein the inhibition transmission power is higher than the normal transmission power of the devices such that selection of the same channel is inhibited over a wider area than the normal operating range of the device.
Dependencies are inferred from the claim text.