Performance analysis of the photoparametric up-converter using harmonic balance techniques

The photoparametric amplifier (PPA) operation is based on the non-linear CV characteristics of a photodiode and therefore, the mechanism constituting gain is highly non-linear and different to that in a conventional amplifier/mixer chain. A PPA has been successfully modelled and simulated using a nonlinear microwave simulator to perform harmonics balance analysis, which represented the photodiode model and nonlinear dynamic capacitance behaviour. The simulation predicted a PPA up-conversion gain as high as 27.57 dB, and this agreed with conventional theoretical analysis. In this article, the theory of operation, the device structure of the PPA, and its characteristic are presented.