A CMOS low power, process/temperature variation tolerant RSSI with an integrated AGC loop
A CMOS Low Power, Process/Temperature Variation Tolerant RSSIwith Integrated AGC Loop

A low voltage low power CMOS limiter and received signal strength indicator (RSSI) with integrated automatic gain control (AGC) loop for a short-distance receiver are implemented in SMIC 0.13μm CMOS technology. The RSSI has a dynamic range more than 60dB and the RSSI linearity error is within ±0.5dB for an input power from -65dBm to -8dBm. The RSSI output voltage is from 0.15V to 1V and the slope of the curve is 14.17mV/dB while consuming 1.5mA (I and Q paths) from a 1.2V supply. Auto LNA gain mode selection with combined RSSI function is also presented. Furthermore, with the compensation circuit, the proposed RSSI shows good temperature-independent and good robustness against process variation characteristics.