Single-Sideband Electro-Optical Modulator and Tunable Microwave Photonic Receiver

We report on the study of widely tunable, resonant single-sideband electro-optical modulators based on whispering gallery mode (WGM) resonators, made out of electro-optically active materials. The modulation process involves interaction of different WGM families with an externally applied microwave field. The tunability results from the unequal response of the mode families to either a temperature change or to an applied voltage. We show that the modulator can be used as an efficient microwave photonic receiver that operates either in direct or coherent regime. Due to its resonant nature, the high-Q electro-optical modulator also can be used as a resolution booster for a low-resolution RF spectrum analyzer.