A Modified SweepSAR Mode with Dual Channels for High Resolution and Wide Swath

Abstract

In this study, an imaging mode of the modified SweepSAR is proposed with performance analysis for a high-resolution and wide swath coverage. To reduce the overall antenna size required for the solution of the azimuth ambiguity problem, different pulse repetition frequencies (PRFs) are utilized for different transmitters, respectively. For each imaging mode, system performance parameters are used for simulation, analysis, wide swath prediction, and comparison between conventional ScanSAR mode and SweepSAR mode based on scanon-receive (SCORE). The system parameters of AASR, RASR, and NESZ will be estimated and suggested on the imaging mode by using appropriate reflector antenna with the effectiveness of a modified SweepSAR employing dual channels.

Performance Evaluation of a Modified SweepSAR Mode for Quad-Pol Application in SAR Systems

“…In other words, each channel operates simultaneously with different PRFs. Two channels continuously observe the total swath with one of the two frequency bands within the total available bandwidth and filtering is performed to reduce interference [6,14]. The operational concepts of the three wide-swath modes (ScanSAR, SweepSAR, and M-SweepSAR) are shown in Fig.…”

“…In this research, we selected a spaceborne SAR system with a C-band center frequency operating at an altitude of 505 km with a total swath width of 150 km for a single-pol mode at an incidence angle of 20°-35° [6]. In this case, we assumed that the SAR system performance, which involves an ambiguity ratio in each direction and the resolution should be under the conditions of −20 dB and 10 m, respectively.…”

“…To overcome this constraint, many operation modes are currently being studied as high-resolution wideswath (HRWS) systems. Among these systems, we are interested in HRWS systems using a reflector antenna [4][5][6]. Generally, reflector antennas have high gain and moderate bandwidth and can be made light-weight by using composite material or with a mesh-type design.…”

“…However, this operation mode requires the use of a low pulse repetition frequency (PRF) to obtain an unambiguous wide swath. For this reason, a modified mode of SweepSAR using dual channels, which is called M-SweepSAR, was examined for a single polarization (single-pol) SAR system [6].…”

Panel Misalignment Effects on the Radiation Pattern from a Solid Surface Deployable Antenna

“…Reflector antennas in satellites are used in applications such as data transmission and remote sensing because they have the advantage of having more than 30 dB of gain and a broad bandwidth [1,2]. Recently, deployable antennas, which are folded in order to be carried with reduced volume in the launch vehicle and deployed in space, have been widely employed in satellites to accomplish large diameter antennas [3]. A solid surface deployable antenna provides lower surface errors than mesh or inflatable antennas, and it can be operated in a highfrequency range.…”