New timing metric for the frame synchronization in WiMAX OFDMA applications

This paper studies the frame synchronization of Orthogonal Frequency Division Multiple Access-Time Division Duplexing (OFDMA-TDD) systems and proposes a new method for downlink of IEEE 802.16 to improve frame synchronization performance. In this paper, we adapt three existing timing metrics for frame synchronization in OFDM mode of WiMAX. Among the methods considered, it is shown that direct application of these metrics, is not possible for frame synchronization in OFDMA mode of WiMAX. Modifications to these timing metrics are done to adapt them for OFDMA mode. Simulations are conducted for AWGN and frequency selective channels to demonstrate the performance of the modified timing metrics. Simulation results show that the proposed method outperforms the existing algorithms in both frequency selective and AWGN channels and is robust to the range of the timing offsets and carrier frequency offset (CFO).