Truncated power control in code-division multiple-accesscommunications

摘要

We analyze the performance of truncated power control in ancode-division multiple-access (CDMA) communication system. This powerncontrol scheme compensates for propagation gain above a certain cutoffnfade depth: below the cutoff level, data transmission is suspended. Wenassume a channel with fast Rayleigh fading and slow lognormal shadowingnplus path loss, where truncated power control is applied to thenshadowing plus path loss and a RAKE receiver combines the Rayleighnfading multipath components separated by more than a chip time. We findnthat truncated power control exhibits both a power and capacity gain.nThese performance improvements result from the fact that with truncatednpower control, less power is wasted compensating for deep fading, andnmobiles on the cell boundaries cause less interference to adjacentncells. We find that truncated power control is most effective fornchannels with large power fluctuations or with large background noise