−80dBm∼0dBm dynamic range, 30mV/dB detection sensitivity piecewise RSSI for SDR/CR receivers

A high dynamic range, high detection sensitivity piecewise RSSI (received signal strength indicator) for software-defined radio (SDR) and cognitive radio (CR) receivers is proposed. With the reconfigurable limiting amplifiers, the RSSI achieves wide dynamic range and high detection sensitivity simultaneously. Two-path I/Q configuration RSSI structure is adopted to reduce the output voltage glitch. The transfer curve of the RSSI keeps stable under various PVT variations with the help of the self-adaptive bias circuit. The proposed RSSI has been implemented in 65nm CMOS and occupies 0.06 mm² chip area. It consumes a scalable current from 1mA to 2.4mA from 1.2V power supply, dependent on the limiting amplifier setting. The simulated results show that the RSSI can detect the signal strength from -80dBm to 0dBm with 30mV/dB detection sensitivity and maximum 1.4dB linearity error over 100KHz~20MHz input carrier frequency range.