Frame Arrival Detection for Low SNR Frequency Selective Fading Channels

摘要

Frame arrival detection is the first step and of the greatest importance in digital communication systems. In this paper, we consider frame arrival detection issue specifically in the challenging low signal-to-noise ratio (SNR) situation. The proposed training sequence consists of three repeated subsequences, each including a few repeated segments and exhibiting high sparsity in frequency domain. The proposed detection method includes the following two stages: The first matched filtering stage employs the subsequence as the filter coefficient, which perfectly matches the frequency sparsity of the received subsequence and could greatly suppress the uniform background noise. The second stage adopts delayed autocorrelation on the filtered signal to detect the presence of training sequence. It is demonstrated that the proposed method could outperform the classic Schmidl and Cox's method in terms of both miss detection probability and false alarm probability, especially under low SNR condition. We also derive the theoretical analysis for both miss detection and false alarm performance. Finally, numerical results are provided to verify the proposed studies.