Vector calibration of optical reference receivers using a frequency-domain method

A jitter-free vector frequency-domain measurement technique to characterize optical reference receivers is presented. The system is based on a Mach-Zehnder integrated-optic modulator (IOM). Results from this new technique and those obtained by optical impulse and heterodyne methods are compared up to 76 GHz. An IOM down-conversion scheme was used to measure the heterodyne beat frequency to >106 GHz.