Estimating the Complex Impedance of an MUTC Photodetector

This paper derives, and then implements, a maximum likelihood estimation procedure for the equivalent circuit model parameters of a photodetector. Specifically, we consider a frequency domain identification procedure whereby the observed data take the form of a complex frequency response function, here the reflection coefficient, S
₁₁
. Both linear least-squares and maximum likelihood methods are compared in their respective performance. Results are presented for various bias voltages and dc photocurrent.