Receiver noise estimation

Abstract

A power estimator for a Code Division Multiple Access (CDMA) receiver. A noise estimate of a received channel may be made by demodulating a received signal using an empty code or Walsh channel. The noise estimate may also be made by demodulating the Pilot signal in systems where potentially all Walsh codes are assigned to active channels. Where the channels are quadrature phase modulated, the noise estimator may take advantage of the Pilot channel configuration by demodulating only the quadrature element of the Pilot channel. The noise estimator demodulates the Pilot using signal processing stages that statistically correspond to the signal processing performed on traffic channels. The statistics of the processing performed in the noise estimate closely track the statistics of the signal processing performed on the traffic channels.