Multiple-beam interference with coaxial cable analogs of optical arrays

Abstract

We study the interference properties of N coherent oscillators by using an equivalent radiofrequency coaxial cable electrical system consisting of N coaxial cables of different lengths, a 1×N splitter, and a N×1 coupler. The typical multiple-beam interference pattern is measured for several values of N as a function of the frequency. Unlike its optical counterpart, we have to consider the attenuation of the cables. The experimental curves agree well with theory and show the characteristics of multiple-beam interference. This approach represents an inexpensive way of experimentally investigating optical arrays.