关键词: 角反射器, 雷达横截面, 初始定位, 精确定位

Abstract: Accurate positioning of corner reflector (CR) is the precondition to monitor the small deformation. CR can be looked as a better point target and it is expected that the energy remains more or less the same when processing different looks with fractional azimuth and range bandwidth. The intensity, the mean to standard deviation ratio (MSR) of energy and the spectral correlation are used to measure the spectral diversity. The paper begins with the performance of CRs, then describes in detail the intensity image, spectral correlation image and MSR image of CRs in two SAR data: Envisat data and TerraSAR data. Based on these work, we draw the below conclusions: 1)corner reflector is obvious on the intensity image, and its strong reflectance to radar wave tends to be met also by some adjacent pixels. In Envisat data CRs appear as bright targets, and CRs in TerraSAR data show as clear crosses;2)In MSR image CRs signals are too weak to be easily detected;3)One advantage of the correlation measure is that it is "well focused", so in the case of CRs high values, they are typically found only in one pixel, and the correlation value of this pixel is obviously higher than adjacent pixels. Generating the list of coordinates of CRs with the three criteria parameters: high intensity value, high MSR value and high spectral correlation value, respectively, and then analyzing comparatively the CRs' pixels location from different criteria parameters and the corresponding phase information, we can get the results as follows: 1)the intensity is susceptible to disturbance from the background environment, and the CRs pixels located by this parameter are offset when their environment is complex;2)the difference is so small between the CRs' MSR value and the background that it can't detect the CRs;3)compared with the CRs' phase located with correlation parameter and other parameters, the phase of former is more stable, indicating that correlation parameter can locate the CRs accurately.

Key words: corner reflector, radar cross section, initial location, accurate location