| 摘要 |
In an adaptive cluster forming and scheduling method for ad-hoc networks (802.15.4, Zigbee), dependent on received energy level and the detected periods of high and low energy levels, above or below a threshold, it is determined whether a normal traffic situation, a traffic overload situation or a hidden node situation exists. Packet transmission failure is a further criteria for the scheduling method. The clusters consists only of one-hop neighbours. The method comprises: collating measured changes in energy levels received over a transmission channel of a wireless telecommunications network; and determining a current condition of the transmission channel by establishing a conformance of the measured changes with expected changes in energy levels when operating under at least one condition. By collating the actual measured changes in energy levels, an accurate, dynamic indication of the energy levels being experienced on the transmission channel can be determined. Also, by correlating the measured changes of the transmission channel when operating in accordance with a particular condition, the conformance or not of the channel with that condition can be determined in order to provide an accurate indication of the current condition of the transmission channel. This avoids having to rely on historic information which may only be relevant to the condition of the channel at previous points in time or having to rely on empirical information which may not be of sufficiently fine granularity either quantitatively or temporally to enable a detailed assessment of the current condition of the transmission channel to be determined. Also, by measuring changes in energy levels, the cause of any non-conformance with a particular operating condition may be derivable, which may not be possible with other indicators. |
