Research On Signal Acquisition And Processing Technology Of Ocean-observing Radar

The “Maritime Power” has risen to China's national strategy.China has a vast sea area and complicated sea surface conditions.Effective real-time ocean-observing technology has become a key factor affecting marine development.The phase-matched solid-state radar has the characteristics of strong real-time,long range,high precision and good resolution.It has become an essential equipment in the field of ocean observation.Digital processing is an effective means to improve radar performance and improve detection results.Therefore,research on the digital acquisition and processing technology of ocean observation radar has important social and economic value.First,the subject designed the index parameters of the acquisition system.According to the band-pass signal sampling theory,the relevant parameters of the acquisition system are designed,and the signal acquisition platform is built to realize the function of radar IF signal acquisition.Secondly,the subject studied signal preprocessing techniques.The subject carried out analysis and simulation of digital down-conversion technology and pulse compression technology,designed a FIR filter for the digital down converter,and studied the sidelobe suppression of the pulse compression distance.Finally,the effects of noise and sea clutter on radar performance during sea surface target detection are studied,and the algorithm is used to solve this problem.The subject used narrow pulse data splicing technology to solve the dead zone problem of measured signals.And analyze the reasons for the formation of specific points,and carry out the dot-coagulation treatment.The PPI image of the processed data is compared with the feature landmarks in the map to verify the feasibility and accuracy of the signal acquisition and processing scheme.Based on the conclusion of the subject theory research,the signal acquisition system of the sea surface observation radar was designed and tested.The test results show that the system can effectively collect and store radar echo signals digitally.Using the measured data,the digital down-conversion algorithm,pulse compression algorithm and constant false alarm processing algorithm simulation in the subject were verified.The results show that the signal acquisition and processing system designed by this subject can complete the acquisition and processing of the actual signal of the sea observation radar,and can be verified by using PPI image and map feature landmark matching.According to the results of the subject,the design index parameters of the radar digital receiver and the signal processor can be determined.It provides theoretical and data support for the production of digital receivers and signal processors and the implementation of signal processing algorithms.