Preamble Design Using Embedded Signaling for OFDM Broadcast Systems Based on Reduced-Complexity Distance Detection

The second-generation digital terrestrial television broadcasting standard adopts the so-called P1 symbol as the preamble for initial synchronization. The P1 symbol also carries a number of basic transmission parameters, including the fast Fourier transform size and the single-input/single-output as well as multiple-input/single-output mode, to appropriately configure the receiver for carrying out the subsequent processing. In this paper, an improved preamble design is proposed, where a pair of training sequences is inserted in the frequency domain, and their distance is used for transmission parameter signaling. At the receiver, only a low-complexity correlator is required for the detection of the signaling. Both the coarse carrier frequency offset and the signaling can simultaneously be estimated by detecting the aforementioned correlation. Compared with the standardized P1 symbol, the proposed preamble design significantly reduces the complexity of the receiver while retaining high robustness in frequency-selective fading channels. Furthermore, we demonstrate that the proposed preamble design achieves better signaling performance than the standardized P1 symbol despite reducing the numbers of multiplications and additions by about 40% and 20%, respectively.