Dynamic range of a coherent optical spectrum analyzer with discrete signal input

Subject of study . The influence of discrete signal input on the dynamic range (DR) of a coherent optical spectrum analyzer with spatial integration is studied. Aim of study. The aim is to determine how the DR of a coherent optical spectrum analyzer depends on the parameters of the discrete input and develop a method for suppressing the influence of spurious signals by narrowing the operating frequency band. Method. A theoretical analysis of spectrum formation under discrete input is undertaken to develop the spurious signal suppression method, and its results are verified by experiments conducted using a laboratory prototype of the spectrum analyzer. Main results. The penetration of spurious signals from adjacent spectra into the main spectrum under discrete input leads to a reduction in the DR, and the dependence of the DR on the discretization parameters is established. A method is proposed for eliminating the influence of the strongest spurious signals on the DR of the spectrum analyzer by reducing its operating frequency band. Estimates of the DR and experimental data confirming the effectiveness of the proposed approach are obtained. Practical significance. The obtained results can be used to develop optical information processing systems with spatial integration under discrete input of signals.