CHANNEL ESTIMATION IN CDMA COMMUNICATIONS SYSTEMS USING BOTH LOWER POWER PILOT CHANNEL AND HIGHER POWER DATA CHANNEL

摘要

An iterative arrangement of channel estimator (12), a Kalman filter unit (14),and a soft demodulator (16) is provided for producing an estimate of complexgain of a CDMA communications channel carrying data and pilot channels, anddemodulated data of the data channel. An initial channel estimate is producedby the etimator (12) using only the low-power pilot channel. This later isimproved by the iterative process using the data channel. The complex gains isrepresented by a sum of sinusoidal signals with different frequencies andrandomly variable amplitude and phase.