Research And Implementation On Carrier Recovery Algorithm Of DTTB System

In this paper the carrier recovery technology in TDS-OFDM system receiver based on Digital Television Terrestrial Broadcasting is investigated.First of all,the basic principles and the characteristics of OFDM system are introduced briefly. With the aid of coherent demodulation and digital signal processing theory, the influence of carrier frequency offset to wireless OFDM system receiver is analyzed in detail. In OFDM system,CP and PN sequence can be used in carrier recovery. A decimal frequency offset estimation algorithm using CP in time domain and an integer frequency offset estimation algorithm using training sequence in frequency domain are studied. Furthermore, an improved carrier recovery algorithm with high efficiency is proposed based on existed carrier recovery algorithms in TDS-OFDM system. The performance of the proposed algorithm is analyzed and the simulation results show that the proposed algorithm is robust under different channels. Finally, an effective carrier recovery architecture suitable for VLSI implementation in TDS-OFDM system is proposed. And the FPGA test results show that the proposed structure has lower complexity than traditional structure.