Abstract

Dual-frequency lasers (DFLs) are known to provide good quality, 100 % modulated optically carried microwave signals. However, the stability of the beatnote provided by a free-running DFL is not sufficient for direct use in radar systems, and in particular for radar local oscillator distribution. It is thus necessary to phase-lock the beatnote on an external microwave reference. With such a stabilization scheme, extremely narrow line width and low phase noise optically carried microwave signals have been obtained up to 20 GHz [1]. Nevertheless, such a setup requires a microwave synthesizer. In this paper, we report on the stabilization of the beatnote of a DFL on an optical fiber delay line, in a similar way as the one used for the stabilization of a microwave oscillator in Ref. 2.

© 2007 IEEE