Synthetic aperture radar echo simulator and echo simulation processing method

Abstract

The invention belongs to the field of the radar signal processing technology and discloses a synthetic aperture radar echo simulator and an echo simulation processing method. The simulator comprises an FPGA (field programmable gate array) chip, a DDR (double data rate), a power module, an upper computer, a network interface module, a D / A (digital to analog) module, a high-speed interface module and a data logger. The simulation method includes the steps of configuration parameter writing, full scene equivalent scattering coefficient determination, system impact response component determination and time-frequency transformation, time-frequency transformation of emission signals, inverse time-frequency transformation processing, small scene or large scene echo signal output and large scene echo signal playback. The single FPGA chip, the DDR and the data logger are only adopted for the main structure, the echo simulation process is achieved by the aid of assembly line work, and the synthetic aperture radar echo simulator has the advantages of simple system structure, high reliability, capabilities of effectively increasing the simulation speed of SAR (synthetic aperture radar) small scene echo signals, achieving real-time simulation of small scene echoes and being used for large scene echo signal simulation and echo signal playback and output, and the like.

Description

Technical field [0001] The invention belongs to the technical field of radar signal processing, in particular to a synthetic aperture radar (SAR) echo simulator based on a field programmable gate array (FPGA) and a SAR echo simulation processing method. Background technique [0002] Synthetic Aperture Radar (SAR) is a high-resolution microwave imaging radar. Since its appearance in the 1950s, it has achieved rapid development. In order to evaluate the various indicators of the SAR system, a large amount of original echo data is required. If these data are obtained through real airborne SAR and spaceborne SAR, the cost will be very high. Therefore, the required echo simulation method is used to obtain the required data. The original echo data is an important means to solve this problem. [0003] Wang Hongxian of Xidian University and others proposed a "FPGA-based SAR echo simulation fast realization method" ("System Engineering and Electronic Technology", 2010, Vol.32), which uses ...

AI Technical Summary

Problems solved by technology

This technology can complete 6144 echo simulations in a 1000×1000 point scene in only 8 seconds. Although it is thousands of times faster than the traditional PC simulation, the process of this method is that each echo pulse needs to wait for the equivalent of the whole scene. The scattering coefficient is determined, the system shock response is FFT, the transmitted signal is FFT and the results are multiplied, and then the IFFT is performed before the next echo pulse can be processed. Therefore, only a small scene of about 1km×1km can be quickly processed. Simulation, but can not realize the simulation of larger scene echo and echo playback; in addition, since the echo simulation device used in this method is connected by 4 FPGAs through high-speed low-voltage differential signal (LVDS) in pairs, and each FPGA It is also necessary to configure a DDR separately, so not only the system structure is complicated, but also the data interaction is cumbersome, and the reliability of its work is also poor.

Therefore, this method has the complex structure of the echo simulation device used, cumbersome data interaction, small processing capacity, and poor reliability. It can only realize the simulation of small scene echoes, and its simulation speed is still relatively slow, and it cannot It is used for the simulation of large scene echoes and the playback and output of echoes, etc.

Images