A new computationally efficient jitter reduction algorithm in nonlinear spectral line (NSL) synchronizer is proposed. This algorithm reduces pattern jitter or self noise by forcing a waveform containing a previous timing phase information at the input of bandpass filter without using a prefilter. The proposed algorithm works in digital domain. Using simulations for binary and 4-PAM signals in AWGN channel, the performance of the proposed algorithm is evaluated in terms of timing error variance or timing jitter and is compared with the prefiltering algorithm. Computer simulations verify the effectiveness of this local symmetry forcing (LSF) techniques for a digital square synchronizer with raised cosine signaling pulses. The proposed LSF algorithm shows nearly the same performance as the prefiltering algorithm. While the prefiltering algorithm requires as many multiplier as prefilter's tap, the LSF algorithm need constant number of multiplier. Therefore, the proposed LSF algorithm is efficient in hardware complexity. The cost saving without using a prefilter may be significant in VLSI implementations.
