摘要
为增强对OFDM信号的侦察能力,提出一种基于最大循环相关值的OFDM信号检测法,分析了OFDM信号的循环平稳性。分析结果表明,循环相关函数在循环频率轴上具有离散频率峰值,其峰值幅度是保护间隔与OFDM符号长度比的正弦函数。给出了基于循环相关检测的恒虚警接收机结构框图。计算机仿真结果表明,基于循环相关的检测法在理想噪声环境下比传统的能量检测法性能差5 dB,但在噪声不确定的条件下,其检测性能比能量检测法更加稳健。
To enhance the reconnaissance capability of OFDM signals,this paper proposed a novel method of detecting OFDM signals based on maximum cyclic autocorrelation,and analyzed the cyclostationary characteristic of OFDM signal.The analysis results show that the function of cyclic correlation took on discrete frequency peaks in cyclic frequency axis,and the amplitudes of the peaks were the sine function of guard interval and the OFDM symbol length ratio.It presented the structure diagram of the constant false alarm receiver based on maximum cyclic autocorrelation.The computer simulation results demonstrate that in the ideal noise condition the performance of the detection method based on maximum cyclic autocorrelation is 5dB inferior to that of the conventional energy detection method while it is much more robust when the noise is uncertain.
出处
《计算机应用研究》
CSCD
北大核心
2012年第2期714-716,738,共4页
Application Research of Computers
基金
解放军电子工程学院博士创新基金资助项目
