Measurement of small optically pulse-modulated reflection coefficients
Abstract
Platte (1981) has demonstrated that light-sensitive GaAs microstrip structures controlled by fast laser pulses via substrate-edge excitation can be successfully used either as an optically pulse-modulated microwave load or as a high-speed optoelectronic microwave switch. In comparison with top-side excited optoelectronic microstrip devices, the substrate-edge excited modulator exhibits significant improvements of both VSWR and on/off signal ratio. However, there are testing difficulties. These difficulties are related to the impossibility to employ a standard S-parameter test system. There was, therefore, a problem to find a suitable technique for measuring very small input reflection coefficients of which both phase and magnitude are pulse-modulated through laser-pulse-excitation. The present investigation is concerned with a new method for measuring small pulse modulated complex reflection coefficients of which both phase and magnitude are a rapidly varying function of time.
- Publication:
-
Electronics Letters
- Pub Date:
- August 1983
- DOI:
- 10.1049/el:19830426
- Bibcode:
- 1983ElL....19..625P
- Keywords:
-
- Light Modulation;
- Optical Measurement;
- Optical Reflection;
- Pulse Modulation;
- Spectral Reflectance;
- Gallium Arsenides;
- Laser Outputs;
- Microstrip Devices;
- Photonics;
- Standing Wave Ratios;
- Time Functions;
- Electronics and Electrical Engineering