A new spaceborne wide swath sliding spotlight mode with a high squint angle

The spaceborne squint sliding spotlight mode provides the capacity to observe the Earth in high resolution with different angles. However, with the increased squint angle, the imaged swath is obviously reduced due to the large range cell migration. To extend the reduced swath, a new spaceborne wide swath sliding spotlight mode with a high squint angle is proposed in this paper. Besides azimuth beam steering to improve the azimuth resolution, antenna beam is also steered in elevation to improve the swath width. The imaging principle of the proposed imaging mode is described in detail, while its corresponding flowcharts of SAR system design and imaging processing are given. Furthermore, the beam steering law of the designed system example with azimuth resolution of 0.5m and swath width of 20km is given, while the imaging result of the designed scene with three targets is given. Both simulation results validate the proposed imaging mode in the high squint case.