A low complexity frequency offset detecting algorithm for diversity receiver

This paper presents a new low complexity frequency offset detecting algorithm which can be applied in the diversity receiver system over the flat fading channel. Generally the conventional frequency offset estimation requires the training data to compute the particular value of the carrier frequency offset. However, by utilizing the FLL (frequency locked loop), this algorithm only need to detect the datapsilas symbol information from each receiverpsilas signal to trace the frequency offset. When the transmitter adopts the QPSK modulation, it can work without training data. In addition, only by adding a few hardware resources the frequency offset detection and the phase offset estimation can be considered simultaneously. It not only reduces the computational complexity and simplifies the implementation greatly but also guarantees the tracing precision. Finally the simulation results show that the demodulation performance is improved a lot after this offset compensation.