Broadband Frequency-Modulated Continuous-Wave Signal Generation by Optical Modulation Technique

Optical frequency-modulated continuous-wave (FM-CW) signal generation with a bandwidth of 35 GHz and a pulse duration of 1 μs in the range of 75-110 GHz is demonstrated with an optical frequency multiplier consisting of an optical modulator and optical filters. The FM-CW signal generator is used as a signal source for the surveillance of obstacles and debris in a large area by a distributed radar system connected to the optical fiber network. The system for millimeter-wave FM-CW signal generation is realized using the functions of a multi-frequency band and segmentation of the radar heads with several channels to avoid radio-frequency interference. The wavelength-division multiplexing technology with simple optical heterodyning aids in realizing these functions with high availability.