Abstract: A new Orthogonal Fre-quency Division Multiplexing(OFDM) signal structure is constructed by using the same PN sequence as guard interval for Time Domain Synchronous Orthogonal Fre-quency Division Multiplexing(TDS-OFDM) system. A low- complexity PN subtraction and signal detection algorithm is proposed based on FFT. The complexity of the algorithm is similar to that of the regular Cyclic Prefix OFDM(CP-OFDM) without complex FIR equalizer. Because some noises in guard interval are introduced to the signal detection, the BER performance of the algorithm degrades compared with that of CP-OFDM. Simulation results show that their BER performance difference is less than 0.1 dB in typical 2-path HF channel, while the performance difference is less than 1 dB in 4-path HF channel whoes time spread is relatively large.

Key words: signal detection, Time Domain Synchronous Orthogonal Fre-quency Division Multiplexing(TDS-OFDM), Cyclic Prefix OFDM(CP-OFDM)

摘要： 构造一种在所有正交频分复用(OFDM)符号中使用同一PN序列作为保护间隔的时域同步OFDM信号格式，提出一种基于快速傅里叶变换的PN码干扰消除和信号检测算法，该算法不使用FIR均衡技术，复杂度低，仅与常规CP-OFDM信号检测算法的复杂度相当，但由于引入了部分保护间隔内的噪声，因此BER性能不如CP-OFDM系统。仿真结果表明，在典型的双径短波信道中，两者的BER性能差距小于0.1 dB，在信道时域扩展较大的四径短波信道中，两者的BER性能差距小于1 dB。

关键词: 信号检测, 时域同步正交频分复用, 基于循环前缀的OFDM

CLC Number: 

• TP301.6