Research On Photon Microwave Waveform Transformation Based On Time Domain Operatio

Microwave arbitrary waveform is widely used in signal processing,radar and sensors.The traditional microwave waveforms generation and transformation are realized by electronic systems.However,due to the low speed and limited bandwidth of electronic devices,they can not satisfy the needs of modern communication systems.Photonic technology has the advantages of high speed and wide bandwidth,and it can easily overcome the bandwidth constraints that electronic devices are difficult to solve.Aiming at the key technology of photonic microwave waveform transformation,this paper makes a theoretical and experimental research on the photonic microwave waveform transformation,which is based on signal envelope function operation in time domain.At first,we introduced the research background and significance of all-optical microwave waveforms generation and transformation.The principle and research status of photonic microwave waveform generation and transformation in recent years are summarized.Secondly,the key processors of waveform transformation,such as multiplier and differentiator,are introduced in detail,including their definition,classification,implementation principle and important applications.Finally,several all-photonic approaches of microwave waveforms generation and transformation are proposed,and these schemes are verified by theory,simulation and experiment.In addition,the relationship between time delay and fitting coefficient of the differential method,which is based on the mathematical definition of differentiation,is analyzed theoretically.For this kind of differential method,which is based on phase modulation cascading a filter with linear edge,the theoretical derivation is further completed when the phase modulation detection light is an intensity function waveform,and the theoretical analysis and application of this kind of differential method are further expanded and completed.In experiment,an initial triangular pulse is transformed into square pulse and sawtooth(or reversed-sawtooth)pulse via two types of differentiators with different rules of operation,respectively.In addition,by using a SOA as a multiplier,both bright and dark parabolic pulses are achieved,which are further transformed into sawtooth(or reversed-sawtooth)pulse by taking the first derivative operation.The scheme is intuitionistic in mathematics and can be adjusted visually in experiment.Furthermore,it not only provides a novel technological approach to implement all-optical microwave waveforms generation,transformation and computing,but also exhibits a new idea for the future realization of integrated high-speed all-optical signal processing and communication system.