OFDM系统中基于符号间相位差分调制的频偏估计模糊度校正算法

Frequency Ambiguity Resolution Algorithm for OFDM Systems Based on Phase Differential Modulation between Adjacent Symbols

OFDM系统的性能对频率偏移非常敏感。该文针对OFDM系统频偏估计中所产生的模糊度问题提出了一种基于符号间相位差分调制的频偏估计模糊度校正算法。它通过在相邻OFDM符号中相同子载波间进行相位差分调制来校正频偏估计模糊度。文中从理论上给出并证明了算法具有唯 可辨识性的充分条件,并分析比较了算法的复杂度和定时误差对算法性能的影响。理论分析和仿真结果表明,在性能相近的前提下,该文提出的频偏估计模糊度校正算法具有运算量小和对定时误差不敏感的优点。

OFDM systems are sensitive to the frequency offset. In this paper, a novel frequency ambiguity resolution algorithm in OFDM systems based on phase differential modulation between adjacent symbols is proposed to correct the frequency ambiguity. The sufficient condition for the proposed algorithm to achieve unique identifiability is deduced. Moreover, the computational complexity of the proposed algorithm and the sensitivity of the proposed algorithm to the timing error are also analyzed in the paper. Theoretical analysis and computer simulations show that the proposed algorithm has the low complexity advantage over conventional algorithm while maintaining approximately the same performance.