Procedure and device for the evaluation of optical signals using a gated modulation source and an optical delay circuit to maintain a self-homodyne receiver.

摘要

To observe the spectrum of an optical signal (12) it is selectively modulated (14) between an unmodulated and a modulated state, routed to an optical conduit (24) in parallel with an optical delay line (26) the two states thus being mixed together, the unmodulated state of the optical signal serving as a local oscillator signal. The parallel combination of the optical conduit and the optical delay line together with a photodetector (30) functions as a self-homodyne receiver. The self-homodyned mixing of the unmodulated and modulated states of the optical signal produced by the optical source serves to frequency-translate the optical power spectrum to within the bandwith of an analyzer (32) such as a microwave spectrum analyzer