Photonic-Aid Flexible Frequency-Hopping Signal Generator Based on Optical Comb Filtering

A novel photonic-aided approach for generating flexible frequency hopping (FH) signals using optical comb filtering (OCF) is proposed and investigated. Wavelength selection, controlled by an intermediate-frequency (IF) signal, is achieved by leveraging the arithmetic progression of frequency differences between the OCF passband and the OFC comb lines. After optical heterodyne mixing of the selected wavelengths with the IF-FH signals, ultra-wideband and flexible FH signals are generated. Theoretical analysis and simulations are carried out to demonstrate the generation of 5-level, 10-level, and 25-level stepped frequency and Costas FH signals, as well as more complex signals like a 30 GHz LFM signal and a 24 GHz sinusoidal chirped signal. The effects of laser frequency offset and system parameter selection are also discussed. This approach, offering wide bandwidth, flexible tuning, good stability, and integration potential, is promising for applications in cognitive radio, modern radar systems, and electronic warfare.