A Fast and Accurate Automatic Gain Control for a Wireless Local Area Network Receiver

In this paper we analyze the automatic gain control (AGC) of an IEEE standard 802.11a compliant wireless local area network (WLAN) receiver. We show an efficient method to solve the problem of obtaining accurate and fast power estimates of the input signal for a huge dynamic range. In particular, we use a mixed signal approach, which has the further advantage of low power consumption. With these estimates we adjust the gains of the amplifiers to obtain the best possible signal at the analog-todigital converters (ADCs) in the WLAN receiver. We discuss the functionality of the AGC and analyze the implemented analog and digital power estimators. For the introduced components, we provide bitand cycle-true simulation results.