OFDM系统中基于盲检测的低复杂度分块SLM算法

Low complexity block SLM based on blind detection in OFDM systems

为了降低正交频分复用(orthogonal frequency division multiplexing,OFDM)系统中传统选择性映射(conventional selected mapping,CSLM)算法的计算复杂度,提高系统的频谱利用效率,提出了一种基于盲检测的低复杂度分块选择性映射(block selected mapping,BSLM)算法,发送端利用逆快速傅里叶反变换(inverse fast fourier transform,IFFT)性质仅需少量低维IFFT运算即可获得较多的备选序列,接收端采用低复杂度的盲检测方式。仿真分析了所提算法的峰均功率比(peak to average power ratio,PAPR)、立方度量(cubic metric,CM)和误比特率(bit error rate,BER)性能。结果表明,所提算法不仅明显降低了计算复杂度,而且有效抑制了OFDM信号的PAPR和CM,获得与已知边带信息的CSLM算法相近的BER性能。

In order to reduce the computational complexity and improve the spectrum efficiency of the conventional selected mapping（CSLM）algorithm in orthogonal frequency division multiplexing（OFDM）systems,a low complexity block selected mapping（BSLM）algorithm based on blind detection is proposed.In the method,the transmitting part only needs a few low-dimensional inverse fast fourier transform（IFFT）operations to obtain a lot of alternative sequences,at the same time,the receiving part uses a modified blind detection to reduce the complexity.The performance of the peak to average power rate（PAPR）,cubic metric（CM）and bite error rate（BER）is analyzed.Simulations show that the proposed method can not only reduce the computational complexity significantly,but also control PAPR and CM of the OFDM signal effectively,as well as it can obtain similar BER performance to that of the conventional SLM with perfect side information.