Transient Noise and Gain Characterization for Pulse-Operated LNAs

We propose a novel method for direct characterization of transient noise and gain for a pulsed low-noise amplifier (LNA) with nanosecond resolution over a wide bandwidth. The method used a standard noise source and an oscilloscope to measure the time-domain output waveform of the LNA. Transient noise and gain of a gate-pulse-operated C-band LNA at two biases were measured with 50-ns resolution. The method showed good agreement with static measurements. The transient gain was compared with transient S-parameter and drain current measurements, which confirmed the proposed method.