Target detection is an important research content in the radar field.At present,efforts are being made to optimize the precision of detection information.In this paper,we use the high pulse repetition frequency(HPRF)t...Target detection is an important research content in the radar field.At present,efforts are being made to optimize the precision of detection information.In this paper,we use the high pulse repetition frequency(HPRF)transmission method and orthogonal biphase coded signals in each pulse to avoid velocity ambiguity and range ambiguity of radar detection.In addition,We also apply Walsh matrix and genetic algorithm(GA)to generate satisfying orthogonal biphase coded signals with low auto-correlation sidelobe peak and cross-correlation peak,which make the results more accurate.In a radar receiver,data rearrangement of echo signals is performed,and then pulse compression and moving target detection(MTD)are utilized to get the final velocity and range information of a target without velocity ambiguity and range ambiguity.Besides,a small transmitting pulse time width is adopted to reduce the working blind area,and two different high pulse repetition frequencies(HPRFs)are adopted to solve the problem of range eclipse.Simulation results finally prove the effectiveness and feasibility of the proposed method.展开更多
Target vdocity and acceleration are two of the most important features for identification of warheads and decoys in ballistic missile defense phased array radar systems. Velocity compensation is also the necessary ste...Target vdocity and acceleration are two of the most important features for identification of warheads and decoys in ballistic missile defense phased array radar systems. Velocity compensation is also the necessary step for one-dimensional range profile imaging. According to the high-vdocity characteristics of ballistic objects and the low data rate of phased array radars with multiple target tracking, a fine spectral line digital velocity tracking frame is presented and a new method is developed to extract velocity error and resolve the velocity ambiguity in the measurement loop. Simulation results demonstrate the effectiveness of the proposed technique.展开更多
The removal of noise and velocity ambiguity and retrieval and verification of horizontal wind field is a prerequisite to make the best and fullest use of Doppler radar measurements. This approach was applied to the Do...The removal of noise and velocity ambiguity and retrieval and verification of horizontal wind field is a prerequisite to make the best and fullest use of Doppler radar measurements. This approach was applied to the Doppler radar data collected during August 2005 for a landing typhoon Matsa (0509) in Yantai, Shangdong Province, and the verified result shows that the quality control for this dataset was successful. The horizontal wind field was retrieved and then verified by studying the characteristics of the radar radial velocity and large-scale wind field and the vertical cross section of the radial velocity determined with the typhoon center as the circle center and comparing it with satellite imagery. The results show that the meso- and small-scale systems in Matsa and its horizontal and vertical structure could be clearly retrieved using the dataset collected by single Doppler radar, and a shear or a convergence was corresponding with a band of severe storm around Matsa. At the same time, the retrieved wind field from single Doppler radar is proved to be a reliable and high-resolution dataset in analyzing the inner meso-scale structure of Matsa. It is also proved that the method for removing the velocity ambiguity could be an effective approach for preliminary quality control of the Doppler radar data, and the VAP method could also be a reasonable solution for the analysis of mesoscale wind field.展开更多
基金supported by the Special Science Foundation of Quzhou(2020D007,2021D009).
文摘Target detection is an important research content in the radar field.At present,efforts are being made to optimize the precision of detection information.In this paper,we use the high pulse repetition frequency(HPRF)transmission method and orthogonal biphase coded signals in each pulse to avoid velocity ambiguity and range ambiguity of radar detection.In addition,We also apply Walsh matrix and genetic algorithm(GA)to generate satisfying orthogonal biphase coded signals with low auto-correlation sidelobe peak and cross-correlation peak,which make the results more accurate.In a radar receiver,data rearrangement of echo signals is performed,and then pulse compression and moving target detection(MTD)are utilized to get the final velocity and range information of a target without velocity ambiguity and range ambiguity.Besides,a small transmitting pulse time width is adopted to reduce the working blind area,and two different high pulse repetition frequencies(HPRFs)are adopted to solve the problem of range eclipse.Simulation results finally prove the effectiveness and feasibility of the proposed method.
文摘Target vdocity and acceleration are two of the most important features for identification of warheads and decoys in ballistic missile defense phased array radar systems. Velocity compensation is also the necessary step for one-dimensional range profile imaging. According to the high-vdocity characteristics of ballistic objects and the low data rate of phased array radars with multiple target tracking, a fine spectral line digital velocity tracking frame is presented and a new method is developed to extract velocity error and resolve the velocity ambiguity in the measurement loop. Simulation results demonstrate the effectiveness of the proposed technique.
文摘The removal of noise and velocity ambiguity and retrieval and verification of horizontal wind field is a prerequisite to make the best and fullest use of Doppler radar measurements. This approach was applied to the Doppler radar data collected during August 2005 for a landing typhoon Matsa (0509) in Yantai, Shangdong Province, and the verified result shows that the quality control for this dataset was successful. The horizontal wind field was retrieved and then verified by studying the characteristics of the radar radial velocity and large-scale wind field and the vertical cross section of the radial velocity determined with the typhoon center as the circle center and comparing it with satellite imagery. The results show that the meso- and small-scale systems in Matsa and its horizontal and vertical structure could be clearly retrieved using the dataset collected by single Doppler radar, and a shear or a convergence was corresponding with a band of severe storm around Matsa. At the same time, the retrieved wind field from single Doppler radar is proved to be a reliable and high-resolution dataset in analyzing the inner meso-scale structure of Matsa. It is also proved that the method for removing the velocity ambiguity could be an effective approach for preliminary quality control of the Doppler radar data, and the VAP method could also be a reasonable solution for the analysis of mesoscale wind field.
