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Synthetic Aperture Radar now is widely used in remote imaging which have many kinds of system. But as SAR data become larger and larger, the traditional Digital Signal Processing processor can not afford the high speed and high resolution process in rated size and power. But our optical processor for SAR can finish the data process in high speed because it can perform the Fourier transformation at...
The core problem of microwave imaging is to acquire high azimuth resolution. The universal solution is synthetic aperture radar (SAR) utilizing the relative movement between radar and target scene. Recently some researchers propose a novel imaging scheme called microwave staring imaging for motionless platform based on wavefront modulation in azimuth. However, it's not suitable for low-speed platform...
The airport detection based on the Synthetic aperture radar (SAR) image is of great importance for both military and civil applications. Typically, the airport is characterized by the airport runway appearing as the black elongated rectangle in the SAR image. The airport detection, which aims to find the elongated rectangles with specific length and width, poses high demands on the spatial resolution...
In this paper, we proposed a clutter suppression algorithm for SAR imaging due to different target power spectrum density (PSD) and clutter PSD in azimuth direction. The optimal waveform of the SAR system is designed according to the prior-knowledge of the target and clutter, an amplitude limiter set in frequency domain is used to suppress the clutter response and 2-dimentional pulse compression is...
An automatic DPCA technique is presented for SAR Ground Moving Target Indication (GMTI). We note that there exists a shift and a phase difference between the images from two channels. Therefore, SAR-GMTI can be implemented in the following steps: Image registration, phase compensation, image subtraction, and CFAR detection. In our technique, these steps are carried out automatically, and thus no precise...
Synthetic Aperture Radar (SAR) is a powerful tool for alltime and all-weather imaging. As the technology developed, the resolution of SAR image is required much higher, and the processing time is required shorter. Traditional DSP processor is difficult to process the high resolution complex SAR data of 3 meter and 1 meter, or even high. The optical processor performs the most promising capability,...
Microwave staring imaging scheme based on range pulse compression and azimuth wavefront modulation is a new radar scheme. Under the condition of no relative motion between radar and scene, the scheme can obtain radar images with high resolution in both range direction and azimuth direction. The paper presents this imaging technique by theoretical analysis and simulation. Microwave staring imaging...
A clutter suppression algorithm for SAR imaging is proposed in this paper. The optimal waveform of the SAR system is designed according to the prior-knowledge of the target and clutter, an amplitude limiter set in frequency domain is used to suppress the clutter response and 2-dimentional pulse compression is then used to the SAR imaging. With the help of this algorithm, the SAR sensor has a strong...
An innovative algorithm to reconstruct complex target-induced azimuth envelope in synthetic aperture radar (SAR) system is proposed. Unlike the assumption in conventional SAR imaging algorithms, target's backscattering coefficient can hardly remain constant when synthetic aperture time is long enough. In order to fully understand the target feature, we extract both amplitude and phase information...
Synthetic aperture radar (SAR) is an active microwave sensor which is able to produce high-resolution images with day and night capability. Traditionally, the image quality assessment of the SAR system is described by the response function of an isolated point target. However, some man-made targets which are placed together can not be distinguished clearly. As the point target has the characteristic...
Optronic processing is a promising way to real-time highresolution SAR image formation. Rang migration is inevitable in SAR imaging, especially in the case of highresolution SAR system, range cell migration correction (RCMC) is considered in nature. A solution of RCMC by using optronic processing is presented in this paper. In this optronic solution, most computation is undertaken by optical devices,...
This paper uses ray tracing technique to simulate a complete imaging process of Synthetic Aperture Radar (SAR). The simulator can collect the raw data and generate accurate shadows of the object. The radiation pattern is defined by a spotlight to have more realistic imaging effect. Considering the high performance computing of modern graphics processing units (GPU), we transfer the ray tracing algorithm...
Here feature extraction of a generic SAR target is studied. We apply a new data model to target feature extraction and improve SAR image quality. The data model we construct contains (1) envelope, (2) location of the target. The envelope shape can be controlled by four parameters, and location information is indicated by frequency pair in both range and cross-range. These parameters would be estimated...
Synthetic aperture radar (SAR) is an active microwave sensor which is able to produce high-resolution images of the earth surface, with all-weather day and night capability. Conventionally, SAR image quality assessment is typically done by evaluating the signal of the corner reflectors which are positioned in the scenery, and a specialist is needed to extract some characteristic parameters (e.g. the...
Onboard SAR data imaging is increasingly important for many satellite applications. And optical SAR processor is one promising solution due to its extremely quick calculation speed, simple structure and strong radiation hardness. Recent relative researches done by researchers of National Optics Institute in Canada prove the feasibility of optical processor, but its resolution of 30 meter is relatively...
In this paper, we apply the optimum waveform design method to meet the application of elastic targets detection and aim at enhance the target detection rate. The target is assumed to be Gaussian elastic targets and the clutter is assumed to be a stationary Gaussian random process. The detection problem then is described using Neyman-Pearson Detector. The waveform design solutions for elastic targets...
In this paper we analyze the problem of waveform design for target detection in the presence of clutter and noise environment. We use the target priori characteristics to design the transmitted waveform. The waveform is designed by mutual information criterion. Firstly, we present the signal model and information theoretic approach to design waveform. Secondly, we discuss the waveform design is the...
This paper presents a novel and compressive SAR raw data simulator based on CUDA via GPU. The stripmap synthetic aperture radar(SAR) is introduced to model antenna illumination behavior. Compared with conventional raw data simulators, we no longer limit our research interests on a single point target's raw data simulation, but expend it to that of complex scene. In order to compensate the greatly...
A new algorithm for complex-valued SAR images compression is proposed in this paper. A complex-valued SAR image consists of a magnitude part and a phase part, and in this paper the two parts are compressed separately. For the magnitude part, it is compressed by JPGE2000 algorithm, while for the phase part, it is compressed by the proposed adaptive quantization method. The phase quantization is adaptive...
A comprehensive and novel SAR echo simulation method for a great deal of scattering cells is presented in this paper. In order to greatly reduce the processing time, we apply the Graphics Processing Units (GPU). Modern GPUs are very efficient at manipulating computer graphics, and their highly parallel structure makes them more effective than general-purpose CPUs in processing large blocks of data...
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