Endoscopic Real–Time Electro–Optic Sensing System for High–Power RF Signal Measurement

Metal- and semiconductor-based sensors can show distortion and degradation performance when they measure high frequency and high power radio-frequency (RF) signal. Few specialized differential probes for high RF output power measurement have a maximum corresponding frequency of about 10 GHz. On the other hand, commercial field probes and detectors support very high frequency RF signal measurement, but those are only for low output-power measurement. Thus, an RF power introduced into the probes and detectors must be reduced by attenuators and couplers in order to measure high RF power. Nevertheless, the reliability of the measurement is not good due to nonlinear characteristics of the attenuators. In this paper, we propose an endoscopic real-time electro-optical sensor with a photonic assisted circuit for high power Ka-band RF signal measurement to overcome the limitations of present sensors.