Generation And Processing Of Microwave Photonic Pulse Compression Signal And Photonic Integration

With the increasing complexity of electromagnetic environment,radar gradually tends to develop in multiple directions such as large bandwidth,multi-function,multi-band and miniaturization.The traditional radar signal generation technology in electric domain is limited by the electronic rate,and gradually appears a development bottleneck,which cannot meet the needs of modern radar systems.Microwave photonics technology integrates the advantages of both microwave technology and photonics technology,with the advantages of high frequency,large bandwidth,and free from electromagnetic interference.The pulse compression technology based on microwave photonics can generate large time and wide bandwidth radar signals,which is one of the key technologies for radar signal generation.However,the number of pulse compression signal bands and functions generated currently are relatively single,and the traditional microwave photon radar system is based on discrete optical components,so the system is bulky and has low reliability.To address the above issues,this thesis thoroughly investigates the multi-band and multifunctional pulse compression signal generation technology based on microwave photonics,three pulse compression signal generation schemes are proposed,detailed theoretical analysis and simulation verification of these schemes are carried out,and photonic integration feasibility studies are conducted for each scheme.the main research contents are as follows:1.Microwave photonics and modern radar system development are presented,the current research status of multi-band phase-coded signals,multi-band linear frequency modulation(LFM)signal generation techniques,and photonic integration techniques are described,and pulse compression techniques and key devices used in the paper are examined in detail.2.An up,down,and dual-chirped LFM signal generation scheme based on an dual parallel orthogonal keying modulator(DP-QPSK)modulator is proposed.The scheme can generate up-chirped,down-chirped or dual-chirped LFM signals by adjusting the main tuning of the upper DPMZM of the DP-QPSK modulator.The scheme has good flexibility with adjustable frequency and variable chirp form.The up-chirped LFM signal at11GHz-12 GHz,the down-chirped LFM signal at 8GHz-9GHz and the dual-chirped LFM signal at 8GHz-9GHz,11GHz-12 GHz are generated in the simulation.The feasibility of photonic integration of the scheme is also verified in the Opt Sim photonic integration simulation software.3.A multi-band LFM signal generation scheme based on a DP-QPSK is proposed.This scheme can generate quad-band LFM signals or dual-band LFM signals.By adjusting the center frequencies of the two RF sources and the initial frequency and bandwidth of the baseband LFM signal,the LFM signals with different bands can be generated.The simulation generates quad-band LFM signals with 1.5GHz,4.5GHz,6.5GHz and 9.5GHz center frequencies and 1GHz bandwidths respectively,and dual-bands LFM signals with3 GHz and 8GHz center frequencies and 2GHz bandwidth respectively.The feasibility of photonic integration of the scheme is also verified in the Opt Sim photonic integration simulation software.4.A three-band phase coded signal generation scheme based on DP-QPSK modulator is proposed.The phase coded signals with 5GHz,10 GHz and 15 GHz as the center frequencies and 8GHz,16 GHz and 24 GHz as the center frequencies are generated in the simulation,thus realizing the generation of three-band phase coded signals.The scheme has adjustable frequency and simple structure,which has wide application prospect in multi-band radar.The feasibility of photonic integration of the scheme is also verified in the Opt Sim photonic integration simulation software.