On the Spectral Bitrate Loss of Superimposed Pilot and Preamble Synchronization

In present packet-based wireless OFDM systems, such as IEEE802.11a/g, a preamble technique is used to accomplish the synchronization functions. Although this technique is well-developed, delay and bitrate loss due to preamble motivate us to adapt the superimposed pilot technique as an alternative approach for synchronization. In this paper1, we study the spectral bitrate loss due to both techniques and figure out that the length of the superimposed pilot and the ratio of the power of the superimposed pilot to the total power are the most important design parameters to maximize the spectral bitrate of the superimposed pilot technique. Our results show that the spectral bitrate of the superimposed pilot technique is higher than that of the preamble up to the ratio of data OFDM symbol length to total packet length L ′ = 0.95.