A Practical Double Peak Detection Coarse Timing for OFDM in Multipath Channels

For orthogonal frequency division multiplexing (OFDM) systems in multipath channels, the detection of the first path is desirable to avoid inter-symbol-interference (ISI). However, the conventional peak detection of the cyclic prefix (CP) correlation curve can detect the strongest path but not the first path, while the largest slope detection is sensitive to background noise. This paper presents a novel coarse timing algorithm using double peak detection of CP correlation, which is robust to noise and simple to implement in practice. Considering practical hardware impairments like sampling frequency offset (SFO), the performance of the proposed method is verified by simulations.