An improved analysis of an optoelectronic mixer based on a metal-semiconductor-metal photodetector

Abstract

where Rvdc is the experimentally measured dc responsivity of the MSM-PD OEM, A,, n = 0 -N and a are curve-fit-4. M. Cai and H. valid over the full useful range of the MSM-PD OEM, is intended to provide closed-form expressions for L, , CNR,,,, CNR,,,, and F,. Such analytical expressions are essential for evaluating the performance of MSM-PD OEM under different bias, signal, and local-oscillator voltage conditions. ABSTRACT A Fourier-series model for the responsioity of an optoelectronic mixer (OEM) based on a nieial-serniconductor-i?ietal photodiode (MSM-PD) ispresented. The model is zialid oi'er the full usefit1 range of the MSM dc bias rloltage. With the use of this model, closed-form expressions. in terms of the ordinary Bessel functions, are obtained for ihe coniiersion loss, the carrier-io-noise ratio, and the noise figure. 0 1996 John Wiley & Sons, Inc.