Main Characteristics Study of Analog Fiber-Optic Links with Direct and External Modulation in Transmitter Modules

Abstract

The results of experimental studies of the main characteristics of commercially available analog fiber-optic links for microwave signals transmission are presented. The measurements were carried out for transmitters of two types: with direct modulation of Fabry-Perot resonator laser emission intensity through laser injection current modulation and with external modulation of the DFB laser emission intensity in the Mach-Zehnder modulator. Both the optical spectra of the modulated radiation at the transmitter output and the corresponding spectra of signals with a frequency band up to 18 GHz at the output of photodetector modules of analog links have been measured. Special attention was paid to time delay measurements into links' transceiver and receiver modules.