摘要
基于压缩感知的模拟信号采集系统可以解决宽带信号采集困难以及数据量过大的问题,已经成为目前信号采集的重要发展方向。在将该技术应用于通信侦查或频谱监测等接收任务时,接收机所截获的信号实际是处于宽带范围内的多个时域重叠窄带信号的混合,如何快速精确地从压缩信息中估计出各分量的调制参数便成为后续解调的必要条件。针对该问题提出一种基于循环累积量的调制参数估计方法,算法不需要先验信息,在不重构原始信号的前提下,由压缩测量值直接推导出混合信号的循环累积量,利用信号调制参数和循环频率之间的关系,实现对每个信号分量载波频率和码元速率的精确盲估计。实验证明算法针对MPSK、MQAM两种类型的混合信号切实有效,且计算复杂度小、精确度高、抗噪声性能好。
The analog signal acquisition systems based on Compressed Sensing could solve the hard problem in huge data of wide-band signal acquisition, and it became the major development orientation of signal sampling. When it is used in communication reconnaissance or spectrum sensing, the received signal is a mixing of some narrow-band signals within a wide range. Then the modulated parameter estimation of the mixed signals is the key to subsequent signal analysis such as demodulation. The paper proposes a modulation parameter estimation algorithm focusing on cyclic cumulants, and derives the linear relationship between the compressed measurement and the mixed cyclic cumulants. The connection of cyclic frequency and modulated parameters can be applied to estimate the carrier frequency and symbol rate accurately . Simulation results show it has a good performance for the mixed signal which is modulated by MPSK or MQAM, and it costs little but plays well in noisy environment.
出处
《信息工程大学学报》
2013年第2期189-195,共7页
Journal of Information Engineering University
关键词
压缩感知
循环累积量
调制参数估计
压缩测量值
compressed sensing
cyclic cumulants
modulation parameter estimation
compressed measurements
