数字信道化接收机的虚假信号自适应消除

Adaptive Elimination of Spurious Signal in Digital Channelized Receiver

由于暂态效应的影响,数字信道化接收机在信号突变处容易产生虚假信号。为此,提出一种虚假信号自适应消除方法。在该方法中,首先根据同一时刻在各信道的瞬时幅度斜率来判断主信号的类型;普通信号的斜率比较大,而扩谱信号的斜率比较小。在主信道的近端,采用门限比较的方式消除虚假信号;而在主信道的远端,采用相邻信道间的幅度比较来自适应消除虚假信号。最后通过仿真验证,该方法既能够消除虚假信号,同时也能保留非常大的双音动态范围。

As a result of the transient effect,digital channelized receiver may generate the spurious signal when the signal varies instantly.Therefore,the method of adaptive elimination of spurious signal for digital channelized receiver is proposed.In the method,the signal type is firstly estimated based on the instantaneous amplitude gradient among all channels.The ordinary signal has large gradient while the spread-spectrum signal has smaller gradient.In the near distance of the main channel,the threshold comparison is utilized to eliminate the spurious signal;while in the far distance,the amplitudes of adjacent channels are compared to decide whether the signal is spurious or not.Finally,simulations are made to prove that the proposed method can not only eliminate the spurious signal,but also keep a very large two-harmonic dynamic range.