| With the radar technology to the rapid development of mapping and precision imaging direction, More attentions are paid to the research and development of high resolution Radar due to its'potentiality in military and civil application recently. However, the shortcoming of the current high-resolution radar is the azimuth resolution and range resolution does not match, seriously affecting the quality of radar imaging. The azimuth resolution of the general non-synthetic aperture radar is restricted by antenna beam width; such restrictions need to break with azimuth super-resolution technology. Radar researchers have proposed several excellent algorithms on how to enhance angular resolution in recent years, such as CAPON, MUSIC and so forth. However, these algorithms require costly hardware and take the complexity of computation considerably, it is because of this to explore practical, simple and fast super-resolution method has good practical sense.In this dissertation, practical, simple and fast azimuth super-resolution method in non-synthetic aperture radar is researched.This dissertation describes and analyzes two new methods of azimuth super-resolution in non-synthetic aperture radar, including an innovative angular super-resolution technique called Scanned Time/Angle Correlation (STAC) which is proposed recently and deconvolution method and the Deconvolution method which is to start from a system point of view.The main content of this dissertation has been divided into two parts, first part focus on methods of study the STAC method. STAC method is an analog to the pulse compression of the range super-resolution. In this part, STAC technique is introduced and simulated under pseudo-random code modulation, 13-bit barker code modulation and linear frequency modulation firstly. The simulation result indicated correct principle of STAC technique. Then, several realistic situations, such as the code length of Random code in a cycle, different signal-to-noise (SNR) of radar received echo and radar antenna directivity, are analyzed and simulated in STAC technique. After simulation, it is proved that the proposed STAC technique is effective and practical.In the second part of this paper, a new method of the signal processing is described to improve the rader azimuth resolution by deconvolution between the antenna pattern and azimuth echoes of targets on scanning the antenna. In this part, Deconvolution method is introduced and simulated under frequency-domain signal processing and time-domain signal processing firstly. The simulation result indicated that in the large SNR, the use of deconvolution method can yield azimuth resolution that is much less than the width of the antenna beam, but under the condition of low SNR produced larger azimuth error would limite the utility of this method. Finally considering the simulation result mentioned above, an improved method of Wiener filtering is proposed in order to solve the limitation from low SNR. After simulation, it is proved that the improved method is effective and practical. Improved Wiener filtering method is effective for improving the SNR, to a certain extent, eased the stringent requirements of the SNR of the Deconvolution method. |
