Research On Radar Detection Performance In Tropospheric Duct

Tropospheric ducts,widely distributing in the global sea area,have the characteristics of high occurrence probability,small transmission loss and so on.They may make waves propagate in the duct beyond the horizon with smaller loss,thus expanding the scope of radar.They may also lead to electromagnetic blind zone or the introduction of new interference,so as to reduce radar detection performance standard atmospheric environment design of or even failure.Taking the evaporation duct as an example,this paper studies the influence of radar antenna parameters and environmental parameters on radar detection performance,and discusses the method of improving the performance of radar detection in the evaporation duct environment.The main work of this paper is as follows:(1)The propagation of waves in the evaporation duct environment can lead to the discontinuity of the radar detection range.In order to effectively describe the coverage degree of the radar detection space in the evaporation duct caused by the discontinuity,the coverage rate is defined in this paper.(2)The influence of radar antenna parameters and environmental parameters on radar detection performance and the influence of the horizontal heterogeneity of atmospheric correction index on the radar detection performance are studied in this paper,using the theory of Markov process and K-L transform.In addition,the effectiveness of the above methods is verified by the experimental data of sea clutter.(3)For the difficulty in obtaining the modified refractivity index in wide airspace and real-time,the application of stable detection area boundary condition is proposed by optimizing the antenna height to achieve radar larger stable detection optimization.(4)For the difficulty in estimating the radar detection range in tropospheric duct environment in this paper,the definition of weighted detection coverage to describe the degree of coverage of the radar detection in evaporation duct environment is presented,which is adopted to optimize the antenna height with greater probability to achieve larger radar detection coverage rate.This paper mainly focuses on how to improve the performance of radar detection in the evaporation duct environment.Although some research conditions are slightly simple,such as without considering sea grazing angle,and regarding the lower boundary as a calm sea,the research method and obtained results have an important theoretical significance and reference value for improving the radar detection performance in tropospheric duct environment.