Evaluation of environmental noise susceptibility of RF circuits using direct power injection

Susceptibility of radio frequency (RF) circuits against environmental noises was evaluated by way of direct power injection. Measurements performed on a 90-nm 2.45 GHz CMOS RF driver amplifier show that the injection of RF power into on-die p⁺ guard bands creates tones at the primary and up-converted frequencies. Simulation achieves the error of less than 2 dB against the measured susceptibility of -40 dB, with the models of passive impedance networks covering probing tips, die pads, metal wirings, as well as a silicon substrate.