針對數字式自動增益控制環路中包絡檢波需要乘法器，大量耗費系統資源的缺點，提出了一種基于絕對值方法或滑窗最大值法代替模擬檢波方法中的信號的平方運算進行數字包絡檢波的新方法，其結果可以大大減小系統速度和資源之間的矛盾。在對環路進行理論分析的基礎上，進行了環路的計算機仿真，仿真結果說明了兩種方案的可行性，并證明都是高效的，并已實用于數字中頻接收機的數字式自動增益控制環路設計中。

According to the disadvantages of demodulation in digital automatic gain control loop, which needs multipliers and uses much of the system resource, this paper proposed a new method of digital demodulation by means of absolute values or maximal values of slip windows which can substitute the square operation of signals in analog demodulation method. The new method can reduce, to a large extent, the contradiction between the system velocity and resource. Based on the analysis of the loop, the computer simulations are given. The results indicate the feasibility of digital AGC, and they are highly effective. The method has been used in design of digital AGC of digital intermediate frequency receiver.