Masayoshi Tsuchida

System design of wide swath, high resolution, full polarimietoric L-band SAR onboard ALOS-2

This paper describes SAR system design of the Advanced Land Observing Satellite-2 (ALOS-2), which is a next-generation Japanese L-band SAR satellite. Since one of an important mission of ALOS-2 is a global monitoring using its unique frequency of L-band, a capability of wider coverage is required. On the contrary, in the point of disaster monitoring especially for urban area, relatively higher spatial resolution is essential. To comply with such a contradictive requirement of wide swath and high resolution, ALOS-2 utilizes a dual-receive channel (DRC) technique, and achieved a coverage area of up to 50km with a spatial resolution of down to 3m. In the paper, the H/W design of ALOS-2 DRC mode is explained. For a wider coverage of polarimetric observation, ALOS-2 installs the fully redundant and “quad-receive channel” system to full-polarimetric mode, achieving a maximum coverage of 50km at 6m resolution. As an experimental mode, new polarimetric mode called “compact polarimetry” is installed for a wide coverage of polarimetric observation.

An experiment of azimuth ambiguity suppression by multiple receiver apertures with airborne Ku-band synthetic aperture radar

This paper presents an experimental result to demonstrate azimuth ambiguity suppression with the displaced phase center antenna technique that is promising technique to realize the high resolution wide swath imagery for spaceborne synthetic aperture radar (SAR). The dual receiver antenna data was acquired by airborne Ku-band SAR. In this paper, we propose a signal compensation procedure to cope with beam squint for the following coherent signal processing such as the dual channel reconstruction algorithm. The azimuth ambiguity suppression capability is evaluated by comparing the image reconstructed from dual-receiver channel to the single receiver channel image. The experimental result shows significant azimuth ambiguity suppression.

A simulator of synthetic aperture radar images; land, ocean surface, and man-made targets

Synthetic aperture radar (SAR) images are very useful for many applications. However, SAR images require a great deal of experience for the interpretation, since the appearances are very different from optical images. Additionally, the appearances change significantly by the observational condition, such as frequency and incident angle. We propose a SAR image simulating algorithm developed for the aid of the SAR image analysis and training. The simulator is also intended to support the SAR system configuration design by providing the expected images. The main features of the algorithm are the capability of wide area simulation and the low computational costs. The simulated image of 10 km square area is shown and compared with the real image