The Study Of Instantaneous Microwave Frequency Measurement Based On Microwave Photonic Technology

Electronic warfare is the most important form of modern warfare.With the rapid advancement of the electronic level in the military,electronic warfare will play a greater role in the future high-tech war.The microwave frequency measurement technology is one of the key technologies in the electronic warfare.It has received extensive attention.Through the rapid acquisition of the microwave frequency to achieve the goals,such as tracking,early warning,interference and other purposes to enemy.With the rapid development of information technology,traditional electronic microwave frequency measurement technology will become increasingly difficult to increase the bandwidth of electronic systems because of its “electronic bottlenecks”.Even if it is realized,besides the high cost of high-speed microwave electronic devices,the volume and weight of system will also become very significant,seriously affecting its application in practice.With the rapid development of microwave photonic technology,people began to consider the introduction of photonic methods into microwave frequency measurement technology.Microwave photonics is the interaction of optical signal and microwave-band electrical signal.It combines the advantages of optical technology and microwave technology.The microwave frequency measurement technology based microwave photonic has some advantages,such as huge bandwidth,low power loss,and immunity to electromagnetic interference.The use of microwave photonics to break through the electronic bottleneck of traditional electronic devices has attracted widespread attention and recognition.Firstly,this paper introduces the background and research significance of the microwave frequency measurement technology,and introduces the advantages of the microwave frequency measurement scheme based on microwave photonics.Then a simple classification and comparison of microwave frequency schemes based on microwave photonics has been proposed.And the principles of some key devices used in those scheme are described.The principle of the proposed scheme in this paper is described and analyzed.The Brillouin frequency shift,Brillouin gain bandwidth and attenuation spectrum bandwidth are measured by experiments.An optical link system for microwave frequency measurement is set up to measure frequency of the microwave signal under test.In this paper,a microwave frequency measurement scheme based on stimulated Brillouin scattering effect is proposed,and the principle of measurement system is analyzed.The feasibility of measurement system is verified through an experiment.The measurement ranges from 0.5GHz to 27 GHz.By analyzing experimental measurement error,the measurement range is divided into two parts and two different Brillouin frequency shift is used for each part.The measurement error reduces from 30 MHz to 20 MHz.The principle of proposed microwave frequency measurement scheme based on stimulated Brillouin scattering effect is analyzed.The inherent defects of the measurement system are found and an improvement scheme is proposed.A microwave frequency measurement scheme based on power ratio is proposed.The feasibility of the improved scheme was verified by experiment.The measurement ranges from 0.47 GHz to 23 GHz and the maximum measurement error reduces from 20 MHz to 8MHz,which greatly improved the measurement accuracy.