Microwave Frequency Measurement Based On Cascaded Four-wave Mixing

Microwave theories and technologies have been extensively researched and widely applied for civil and defense applications.As one of the fundamental applications,microwave measurements are widely used in fields such as astronomy,communications,medicine,radar systems and etc.Among the various parameters of microwave signals,the frequency of microwave reflects the modulation characteristics,which is the key for signal processing and vector analysis,and has received researcher’s attention.Due to the explosive growth of data traffic,critical challenges are bringing urgent demands to microwave measurements,which may not be achievable using purely electronic solutions.As an emerging research field,microwave photonics has been considered as an implementation of new devices and systems for microwave measurements.Among the numerous functionalities enabled by photonics,microwave measurements based on photonics can provide superior performance in terms of large bandwidth,low loss,and strong immunity to electromagnetic interference(EMI).Thus,lots of frequency measurement techniques based on microwave photonics have been widely researched recently.Among these approaches,the photonic microwave frequency measurement(MFM)system utilizing nonlinear optical mixing is highly attractive owing to the key advantage of performing microwave frequency measurement with no inherent bandwidth limitation,but in order to avoid wavelength overlap of the mixing products,multiple parallel MFM functions has to be achieved at the expense of increasing system complexity.In this thesis,we propose a wideband and low-error microwave frequency measurement using four-wave mixing(FWM)based on the frequency-to-power mapping.After analyzing the principle in detail,we verify the system’s feasibility and performance in experiment and a large,40 GHz measurement bandwidth with a 39.3MHz root-mean-square error is achieved successfully.The proposed measurement system also can eliminate the trade-off between measurement range and resolution.We discuss the monolithically integration of an instantaneous frequency measurement system based on FWM.Combining with theoretical design and simulation,integrated waveguide for FWM is prepared by using chalcogenide materials.We then analyze the performance of the chalcogenide waveguide in experiment.Based on the results,we propose some improvement schemes for the waveguide which lays a foundation for the integrated frequency measurement system.