Design of received signal strength indicators for RF-MIMO systems

This document describes the design of received signal strength indicators (RSSI) for RF-MIMO systems. It covers considerations of system level aspects such as dynamic range and the suiting location of the RSSI and presents the implementation of a fully integrated RSSI circuit for 802.11a compliant diversity receivers. Drawing a total current of 6.1 mA from a 3.3 V supply, this circuit provides a dynamic range of about 35 dB with a high response speed of less than 1.15 µs even under heavy capacitive loading conditions.