On Timing Recovery In TDS-OFDM System

In this paper, we introduce the development of digital multimedia video communications and the basic principle of TDS-OFDM system. An emphasis is on the timing recovery technique to recover the symbol timing using a fixed clock that is not synchronized to the transmitter clock and non-ideal interpolation in the DTMB demodulator. Based on the traditional timing recovery methods, Compensating decimal interval algorithm with Searching and tracking of the correlation peaks of the PN sequences embedded in the signals, and compensating timing-offsets algorithm with poly-phase filter to resist multi-path and improve the performance of the receivers are proposed. On the basis of Matlab Simulation, this paper proposes a family of traditional and optimized polynomial interpolators. And a statistical analysis of timing error detector is presented, which includes the ability of resisting the frequency offset, multi-path and larger timing offsets. Simulation results show that these algorithms provide better synchronization performance under multi-path circumstance and larger sampling offsets. In the end, FPGA circuit is designed.