基于DVB-T的OFDM频偏估计算法及DSP实现

Frequency Offset Estimation Algorithm for OFDM Based on DVB-T and DSP Achieve

由于OFDM调制是基于载波间正交的调制方式,频偏存在会使载波间正交性破坏,进而影响解调和性能。基于DVB-T提出了一种基于时域和频域相结合的频偏估计算法并对性能进行了仿真分析,并结合项目实际给出了DSP实现方法,最后对DSP实现后的数据进行了星座图验证和项目最后ARM接收端接收数据的验证。结果表明此算法对解决DVB-T物理层的频偏非常有效。

The OFDM Modulation is based on orthogonal subcarriers. If frequency offset exists in channel, the orthogonal subcarriers will greatly deteriorate and demodulation result will be incorrect .In this paper, an algorithm based on time domain and frequency domain combine is involved to solve both integral and fractional offsets over fading Channel and then DSP achieve process is given. Finally, many computer simulations and actual data constellation were done to validate the performance of the algorithm. Test results verify the algorithm is very effective to solve frequency offset.