Heterodyne measurement of sidebands and frequency combs: a derivation

TL;DR

This paper provides a mathematical framework for heterodyne measurement of optical frequency combs, enabling the determination of individual tooth amplitude and phase through beatnote analysis with a known local oscillator offset.

Contribution

It introduces a detailed derivation of heterodyne measurement techniques for frequency combs, clarifying how to extract amplitude and phase information of each tooth.

Findings

Amplitude and phase of each comb tooth can be determined from beatnotes.

The derivation clarifies the relationship between beatnotes and comb parameters.

The method applies to signals with many frequency teeth.

Abstract

A mathematical description of heterodyne measurement of an optical frequency comb is presented. It is shown that for a signal beam containing many frequency teeth, the amplitude and phase of each tooth can be determined from the beatnote generated when the signal is interfered with a local oscillator with known offset frequency.