Robust synchronization technique for mobile DTV broadcasting system

Synchronization is considered an important design issue for the implementation of digital television (DTV) receiver, specially for proper reception of multipath distorted signal at low signal to noise ratio (SNR). This challenge is more pronounced in complex multipath channel scenarios and for high mobility applications in presence of carrier frequency offset (CFO). In this paper, time domain correlation technique based on multiple PN-511 sequences is proposed to improve the synchronization performance of DTV broadcasting system that is robust against multipath impairments and CFO. Due to self-resolving capability of the multipath components, proposed synchronization algorithm provides better performance than conventional single PN-511 based algorithm in complex multipath channel. Since only the received adjacent PN-511 sequences are considered in the correlation process, the proposed technique is robust against CFO as well. In addition, the proposed technique provides higher peak-to-noise ratio (PNR), therefore this technique can be effectively used at low SNR conditions. Further, maximum likelihood (ML) estimation for multiple PN-511 based algorithm is carried out to evaluate the feasibility of the proposed algorithm.