Parameter blind estimates of DS/SS signals based on Haar wavelet transforms
Wang Zanji · Journal of Tsinghua University(Science and Technology) · 2006
An algorithm based on the Haar wavelet transform(HWT) was developed for blind estimates of pseudo-random code(PC) rates and symbol periods of direct sequence spread spectrum(DS/SS) signals in low signal to noise ratio environments.The ability of the HWT to characterize and detect phase jumps of DS/SS signals was analyzed to formulate the HWT of DS/SS signals.The characteristics of the HWT spectra of the DS/SS signals were analyzed to extract the two HWT parameters.Simulation results with a data set having 400 symbol lengths and a spread factor of 63 show that the PC rate and symbol period algorithm works well with SNR of-18 dB and-14 dB,with better performance than some representative algorithms.