[Show abstract][Hide abstract] ABSTRACT: Broadband and ultrafast frequency sweep signal generation technique has been desired in radar applications as well as signal sources for ultra-wideband wireless communication . Optical signal generation technique is a possible candidate for ultra-broadband signal generation although all electrical one is difficult to apply due to its bandwidth. In conventional modulation technique, however, an extinction ratio of an optical modulator, which is typically around 20 dB, could require optical filters for rejection of unnecessary harmonics and tones. High extinction ratio (HER) optical modulator with a structure of dual-parallel Mach-Zehnder interferometer (DPMZI) achieved the extinction ratio of 70 dB [2, 3]. Thus, simple and robust system configuration without optical filters can be possible with the modulator. In this paper, we demonstrated ultrafast and broadband electrical frequency chirped signal generation with the bandwidth of 12.8 GHz and the repetition rate of 20 MHz using the HER modulator.
[Show abstract][Hide abstract] ABSTRACT: We successfully demonstrate ultrafast frequency sweep signal generation using the double-sideband suppressed carrier modulation technique with a high-extinction-ratio optical modulator that helps realize clear signals with no filters. The resultant sweep rate was achieved at 3.67 × 10(16) Hz/s with an extinction ratio above 25 dB, which corresponds to a bandwidth of 11 GHz with a pulse duration of 300 ns.
[Show abstract][Hide abstract] ABSTRACT: We successfully demonstrated ultra-wideband frequency chirp signal generation using the DSB-SC modulation technique with pulse duration of 0.5 μs. A high extinction ratio optical modulator helps realize clear signals with no filters.