Two-step automatic gain control algorithm applicable to chirp spread spectrum device

In this paper, we propose a novel automatic gain control (AGC) algorithm, which is applicable to a commercially available chirp-spread-spectrum (CSS) device. Because of the property of long guard time in the CSS, it is difficult to make use of the conventional AGC algorithm which only uses one window size to estimate the power of signal. Due to using only one window size, there is a tradeoff between adaptation time and stability. The proposed AGC algorithm synthetically utilizes large window size and small window size, simultaneously improving the performance of adaptation time and stability.