Article Details

Abstract

Synthetic Aperture Radar (SAR) provides all-weather, day-and-night Earth observation imaging. However, conventional SAR systems operating with a constant Pulse Repetition Frequency (PRF) cannot simultaneously achieve wide-swath coverage and high-resolution imaging. To address this limitation, Staggered SAR and other advanced high-resolution wide-swath SAR modes are proposed. This paper designs a timer dedicated to Staggered SAR, which enables intra-frame variation of the pulse repetition time. This effectively eliminates the fixed blind ranges between sub-swaths inherent to constant pulse repetition time operation, thereby improving SAR image quality. To guarantee high-reliability operation in the space radiation environment, multiple radiation-hardening techniques, including Triple Modular Redundancy (TMR) and periodic refreshing, are incorporated into both the hardware and software designs. The timer software supports on-orbit reconfiguration, which effectively mitigates single-event effects, thus enhancing the operational lifetime and flexibility of the timer and providing technical support for wide-swath SAR missions.

Keywords

Staggered SAR; variable pulse repetition time; radiation-hardened timer; on-orbit reconfiguration; high-resolution wide-swath imaging

References

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About the authors

Guo Yue (1995-), male, Han ethnicity, Jilin native, engineer, master's student, research direction: radar control and computer; Ma Chunyang (1990-), male, Hui ethnic, from Guyuan, Ningxia, senior engineer, master's student, research direction: radar control and computer; Li Siwen (1999-), male, Han ethnicity, from Suzhou, Anhui Province, assistant engineer, master's student, research direction: radar control and computer; Xia Qiwei (2000-), male, Han ethnicity, from Huaibei, Anhui Province, assistant engineer, master's student, research direction: radar control and computer.