A SINGLE-STAGE 3-TERMINAL HETEROJUNCTION BIPOLAR-TRANSISTOR OPTOELECTRONIC MIXER

A high-conversion gain three-terminal heterojunction bipolar transisto r (HBT) optoelectronic mixer has been demonstrated. The maximum obtain ed intrinsic conversion gain was 10.4 dB. The mixing performance was m easured as a function of the de bias of the device and local oscillato r power level. A SPICE-based large signal model was employed to simula te the device. The main nonlinear effects which contributed to the mix ing process were the voltage dependence of the dynamic emitter resista nce, and the variation of the current gain in the saturation regime.