Design And Analysis Of The Testing System For Waveguide Microwave Photonics Devices

With the rapid development of optical communication technology and optoelectronics technology, a new interdisciplinary microwave photonic appeared. As the core component of microwave photonics, microwave photonics links is being used to process and transmit microwave signals.Compared with the conventional microwave links, microwave photonics links has many advantages, such as large bandwidth, low loss, small size, light weight, high immunity against electromagnetic interference, etc. Microwave photonics links has been widely used in optical communication, intelligent transportation, radar, electronic warfare and other fields. The performance of waveguide devices for microwave photonics directly affects the performance of microwave photonics links. So a good testing system for waveguide devices is very important. This thesis mainly studied the testing system for waveguide devices. At the same time, polymer optical waveguide delay lines were measured based on the testing system.First, a small-signal model of the external modulation microwave photonics link was built. The influence of input optical power of the modulator, bias point of the modulator, half-wave voltage of the modulator, responsibility of the photodetector and relative intensity noise figure (RIN) of the laser on the performance of the link was simulated.Next, the design scheme of testing system was put forward. And according to the characteristic of Mach-Zehnder modulators (MZM), a highly stable quadrature point auto control system for MZM based on digital proportional-integral-derivative (PID) algorithm was designed and demonstrated. The results verified that the stability of the output power at quadrature point was improved more than 72 times from 16.3% to 0.223% when the working temperature of modulator varied from 20? to 50?.Finally, a testing system for waveguide devices was constructed. Based on the system, several experiments were performed to demonstrate the theoretical analysis about the microwave photonics link. The optical properties and microwave properties of waveguides with different length were measured. The experimental results are highly consistent with the theoretical value. The uncertainty of the measurements is below 1.1 ps. Analysis of the error sources gives good foundation for the optimization of the performance of the system.