China is moving forward with synthetic aperture radar (SAR) developments for airborne and space-based platforms, to provide an all-weather reconnaissance capability.

Under its "863 Programme" China has been developing SAR technology since 1986. The programme aims to drive forward Chinese capabilities across broad areas aimed at civil and military modernisation. Most SAR work has been performed at the Institute for Remote Sensing Applications, China Aerospace Technology's Institute of Electronics; the China Academy of Space Technology's (CAST) 501 and 504 Research Institutes; the Ministry of Electronic Industry's 14th Research Institute; and the Southwest Institute of Electronic Equipment.

China's first radar satellite is expected to be the HY-1 (Haiyang-1 or Ocean-1), which is set for launch late next year. HY-1 is based on the CAST 986 bus, used for the SJ-5 (Shijian-5) experimental satellite launched in May 1999.

HY-1 is expected to have a 5m resolution from 700km (430 miles) altitude. Chinese sources say the HY-1 is likely to be equipped with a planar SAR similar to that used on Canada's Radarsat. In the past, China has sought Canadian and Russian technology. A second generation of Chinese radar satellite is already in development.

Last July, China Space Science and Technology announced plans for an imaging satellite cluster of four electro-optic sensor-equipped craft and four radar satellites. Such a constellation would allow a twice-daily revisit rate. Taiwan expects the network to be used to assist Chinese military operations, including targeting short-range ballistic missiles and cruise missiles.

As part of its programme, China test flew the JZ-8 SAR on a Cessna Citation in the mid-1990s. The JZ-8 is a 3m-resolution L-band SAR and it has been used to monitor natural disasters and to assist urban planning. A larger system has been fitted to a Tupolev Tu-154M airliner.

Source: Flight International