A 30MHz–2.4GHz CMOS receiver with integrated RF filter and dynamic-range-scalable energy detector for cognitive radio

A 30MHz-2.4GHz CMOS receiver with a highly linear integrated tunable RF filter, as well as with a dynamic-range-scalable RSSI-based energy detector for both whitespace and interference-level sensing, is reported. The test chip, fabricated in 90-nm CMOS process, achieves over 42dB harmonic rejection including seventh-order harmonic without any external device, 67dB gain, 5-8dB NF, +1.7dBm in-band IIP3, and +37dBm IIP2 while drawing only 25-37mA from 1.2V supply.