A novel adaptive channel estimation method in WCDMA system based on least squares

Rayleigh fading channel estimation using time multiplexed pilot symbols in WCDMA system is considered. The WCDMA uplink signal model is established. A novel adaptive channel estimation method based on least squares (ALS) is presented in this paper to meet the simultaneous needs of high speed, low speed, medium speed and varying-speed, and the weighed combination function is introduced to solve this problem. Weight factor is determined by channel changing rate or maximum Doppler frequency. The method of channel changing rate estimation is proposed in this paper, and it has many advantages such as small calculation and robust characteristic. The simulation results reveal that ALS can track and estimate channel parameter of data symbol, and the RAKE receiver with ALS method can perform well under high speed, medium speed, low mobile speed and varying-speed.