A 480 GHz active frequency multiplier-by-four SMMIC

The submillimeter-wave frequency multiplier-by-four consists of the monolithic integrated cascade of a balanced doubler, a cascode buffer amplifier, and a single-ended frequency doubler. Without any post-amplification, an output power of −14.3 dBm is achieved in a 3-dB output frequency range from 435 to more than 480GHz, resulting in a >45GHz bandwidth. The balanced frequency doubler uses a coupled-line Marchand balun to drive a push-push transistor stage with cascode topology.