A Calculation Method of Spaceborne SAR Real-time Imaging Parameters Suitable for Ship Guidance Imaging

Abstract

The invention relates to a method for calculating space-borne SAR real-time imaging parameters suitable for ship-guided imaging, belonging to the technical field of autonomous imaging of low-orbit SAR payload satellites; Step 1, determining the imaging mode, polarization mode and imaging duration of the SAR satellite; Step 2 , setting the number of wave position groups, and the parameters of each wave position group; step 3, selecting the pulse width, bandwidth and PRF frequency division code of each wave position group; calculating the frame length; step 4, analyzing the target ship message to obtain The latitude of the sub-satellite point, the real slant distance and the scanning angle of the antenna beam, select the corresponding fixed parameters of the wave position group; Step 5, calculate the actual number of transmit and receive pulse delays, sampling start time, imaging start time and imaging end time; Step 6: The SAR imaging system completes the microwave imaging of the target ship according to the imaging instruction package; the present invention realizes the real-time SAR imaging within a short period of time (shortened to seconds) when the AIS finds the target ship, and greatly improves the timeliness of marine ship monitoring sex and visibility.

Description

technical field [0001] The invention belongs to the technical field of autonomous imaging of low-orbit SAR payload satellites, and relates to a calculation method for space-borne SAR real-time imaging parameters suitable for ship-guided imaging. Background technique [0002] my country is a big country with a marine territory of more than 3 million square kilometers and rich marine resources. Due to the large number of ports, complex waterways, and changing sea conditions, efficient and accurate ship detection methods are urgently needed to complete tasks such as warship discovery and positioning, sea area ship monitoring, fishing boat monitoring, and ship rescue in distress. Synthetic aperture radar satellites (hereinafter referred to as SAR satellites) have all-weather, all-weather, and large-scale observation capabilities, and can observe the ocean in a macro, long-term, dynamic, and real-time manner. means. [0003] In addition, in order to assist SAR satellites to mon...

AI Technical Summary

Problems solved by technology

However, the current imaging process of satellite SAR payload usually requires the user to analyze the ship message data downloaded by the AIS payload in advance, determine the area where the target ship is located, give the SAR imaging task plan one day in advance, and generate the SAR imaging command package. After the satellite enters the country, The domestic ground control center sends the command packet to the satellite, and then the microwave imaging can only be completed when the satellite revisits the area where the target ship is located. Therefore, it is actually difficult to achieve real-time data fusion of the remote sensing information data of the above two loads, which is not conducive to user use

Images