Detection of WCDMA uplink signal with combination between sliding match and power spectrum

Xiaoping Wang, Jin Yao, Wangang Wang

COMPUTER MODELLING & NEW TECHNOLOGIES 2014 18(4) 95-101

Chongqing City Management College, Chongqing, China

Aiming at problem of WCDMA uplink signal being difficult to be detected under low SNR, this paper proposes a type of algorithm in which sliding match combines with power spectrum to detect WCDMA signal. Firstly, this algorithm estimates desynchronizing point of signal using Frobenius norm. According to desynchronizing point, a whole cycle of information sequence is intercepted. Correlation of OVSF code sequence is utilized in which residual carrier or DC component of signal would come into being while the received OVSF code sequence completely matches with local OVSF code sequence. Then its power spectrum is calculated and sharp spectral peak would appear in the frequency position of power spectrum. Through detecting amplitude and position of spectral peak, frequencies of OVSF code sequence and residual carrier utilized in WCDMA signal could be accurately estimated. Simulation results show that this algorithm rapidly realizes the estimation on OVSF code sequence and desynchronizing point keeps good detection effect and may effectively overcome the influences of residual frequency offset on it.