Research On Microwave Photonic Arbitrary Waveform Generation And Related Technologies

With the development of wireless communication,electronic countermeasures,radar and other technologies,the information transmission rate is facing greater challenges.The demand for high frequency and large bandwidth signals is increasing.When generating and processing high frequency and large bandwidth signals in electronics,it is difficult and costly to generate signals due to the performance of electronic devices.Microwave photonics has attracted wide attention due to its advantages of high frequency,low phase noise and anti-electromagnetic interference.In this paper,we focus on the generation of arbitrary waveform based on microwave photonics,On the one hand,the microwave photonic technology is introduced,and then the existing general scheme of photonic assisted arbitrary waveform is analyzed theoretically.The mathematical model is built and deduced for the temporal pulse shaping,and the problems of temporal pulse shaping are analyzed in detail,and then the arbitrary waveform scheme based on multi-tone signal is proposed;On the other hand,aiming at the demand of radar system for large time-bandwidth product signals,this paper introduces the radar resolution theory,and further introduces how to realize the large bandwidth and large time width of signals in radar system,and leads to the basic theory of matched filtering and pulse compression signals.Phase-coded signal is a kind of pulse compression signal.Aiming at the development trend of modern radar for high frequency and multi-band,the generation scheme of multi-band phase-coded signal is studied.The main innovations and academic contributions of this paper are as follows :1、In this paper,a novel photonic generation method of RF arbitrary waveform based on multi-tone input is proposed for the first time,which aims to an arbitrary RF waveform generation method with high stability and simple operation.By simply adjusting the power value of the harmonic superposition signal,any desired RF waveform can be achieved.The concept verification experiment of generating triangular / square waveform with adjustable duration is carried out.The influence of dispersion mismatch is also studied in detail.The results verify that the method has good waveform stability.2、In this paper,a dual-band phase-coded microwave signal generation method based on dualpolarized binary phase shift keying modulator is proposed for the first time.By properly preset the bias voltage of the modulator,the dual-band phase-coded microwave signal can be obtained by changing the polarity of the corresponding precoding signal.In addition,phase-coded pulses can be directly obtained,and their aperture time can be controlled by applying three-stage precoding signals.The method is simple,compact and stable,and overcomes the power limitation of the precoding signal.