Multi-GI detector with shortened and leakage correlation for the Chinese DTMB system

As Guard Interval (GI), Pseudo Noise (PN) sequence is padded between adjacent data symbols in Chinese digital television terrestrial broadcasting (DTTB) standard. In order to accommodate with versatile applications, three GI modes are recommended with different lengths and formats. Obviously, a robust multi-GI detecting method is a prerequisite for further demodulation, such as frame synchronization, timing recovery, carrier recovery, and channel estimation. A novel multi-GI detector with shortened and leakage correlation (SLC-MGI) is proposed, which adopts a modified Pre-Pos correlation to overcome variable phases defined in DTMB system. Simulation results show that the proposed scheme outperforms the conventional Mixed-MMLS algorithm over both AWGN and multi-path channels, and is robust to frequency offset.