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Mapping
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Overview of CCRS Activities in Asia
Zdenek "Denny" Kalensky, Dr. Kian Fadaie and Les Whitney
Canda Centre for Remote Sensing (CCRS)
Geomatics Canada, Earth Sciences Sector, Natural Resources Canada
588 Booth Street, Ottawa, Onario, Canada KIA 0Y7
Abstract
Canada Centre for Remote Sensing (CCRS) has a long tradition of cooperation with Asian developing countries in strengthening their national remote sensing capacities. This cooperation has included contribution to formulation of the UN-ESCAP Remote Sensing Program for Asia and the Pacific; organization of study programs in Canada for visiting scientists from Asian countries, as well as training courses and workshops in the region; provision of technical assistance for development of national remotes sensing centers and , in particular, for development of capacities for operational application of RADARSAT data. The latter assistance has been implemented under the GlobeSAR program with participation of the following five Asian countries: China, direct RADARSAT data acquisition capacities in the region.
This good cooperation with Asian countries continues and is being further expanded. Its particular feature is close involvement of Canadian remote sensing private sector, comparing some 180 companies at present (1996). This assures not only continuity of strengthening of links among the Canadian and Asian remote sensing companies.
1. Introdution
Over the past twenty years, the Canada Centre for Remote Sensing (CCRS) has been involved in a large number of remote sensing technology transfer activities in Asia. Their overall aim has counties. CCRS activities in Asia have included provision of advisory services on institutional remote sensing infrastructures, in particular on establishment of national remote sensing centers, ground receiving stations and data processing facilities; organization of workshops and training courses; arrangement of study tours to Canada; participation in formulation of regional and national remote sensing projects; as tweet as joint implementation of pilot projects.
Such direct assistant to individual Asian countries has been complemented by a long-standing cooperation between CCRS and UN-ESCAP Space Technology Applications Section. In particular, CCRS scientists have frequently participated in the activities of ESCAP Regional Remote Sensing Programme. CCRS participation in UN regional remote sensing inputs to the Global Map project, initiated and led by the National Geographical Institute of Japan, should also be noted.
Use of satellite remote sensing inmost developing countries of Asia has now passed the promotional stage and is entering the operational phase. Asian countries have succeeded with
Development of effective remote sensing infrastructures at the regional and, in a number of countries, at the national levels. This has been reflected in growing operational use of satellite remote sensing in Asia for mitigation of natural disasters, monitoring of land cover, inventory of inland water bodies, mapping of forest and monitoring deforestation, sustainable management of coastal zones, etc.
While present remote sensing technology is already contributing significantly to more effective management of natural resources and environmental protection, recent new developments and those expected in the near future, will further enhance the role of satellite remote sensing as a primary source of geospatial information describing types, states and changes of vegetation, surface water bodies and land degradation. Such information, when reliable, delivered in timely manner and available in user-friendly format, is essential for successful implementation of sustainable development strategies.
One of the most important recent sensing technological development has been the deployment of earth observation (EO) satellites with microwave remote sensing payloads. Several countries have launched EO satellites with synthetic aperture radar (SAR) imaging system in the framework of their experimental programs for civilian applications of microwave remote sensing. Canada has become the first country to design such a satellite, RADARSAT 1, for operational worldwide use and to operate it on a commercial basis.
EO satellites with microwave remote sensing systems are of particular interest to countries with tropical humid climate because their image data recording capability is not affected by clouds nor by rain. For example, the procurement of image data recorded by EO satellites with optical sensor system over extensive areas of south and Southeast Asia has been hampered by their dependence on cloud free conditions. It sometimes took years to obtain good quality images (e.g. in many parts of Indonesia, such as Kalimantan and Sulawesi). Obviously, such delays are unacceptable for many application, in particular for mitigation of natural disasters.
Recognizing RADARSAT's importance as a new, dependable source of remote sensing data not only for Canada but for all countries, the Canadian Space Agency (CSA), jointly with CCRS and in cooperation with private industry represented by RADARSAT international Inc. (RSI), initiated two international RADARSAT technology transfer programs designed to speed up effective applications of RADARSAT data worldwide: GlobeSAR, and the Applications Development and Research Opportunity (ADRO). Both programs are briefly described in his paper.
2. Radarsat Program
The RADARSAT program consists of three EO satellites with SAR remote sensing payloads. RADARSAT 1 was launched November 4, 1995, RADARSAT 2 is scheduled for launch by the year 2000, and RADARSAT 3 by the year 2005, While RADARSATs 1&2 have partially identical design (Tables 1 &2; Fig. 1), the remote sensing payload of RADARSAT 3 will reflect new technological developments available for operational application at the time of its detail design. A dual-frequency and dual-polarization SAR system, as well as a combination of SAR and multispectral optical remote sensing system are some of the options being considered for the RADARSAT 3 payload.
Figure 1 RADARSAT - 1 SAR Beam Modes
Table 1. RADARSAT -1 Orbit And SAR System Specification
| RADARSAT-1 parameters | |
| Design timeframe | 5 years |
| Orbit geometry | circular, sun-synchronous |
| Orbit altitude | 793km - 821km |
| Orbit inclination | 98° |
| Orbit period | 100.7 minutes |
| Orbit repeat cycle | 24 days |
| Orbit repeat cycle | 14 |
| SAR frequency | 5.3 GHz (C-band) |
| SAR wavelength | 5.6 cm |
| SAR polarization | horizontal in both directions (HH) |
| SAR antenna | steerable, right looking |
| SAR recording time capacity | 28 minutes per each orbit |
| SAR on-board data recording | 2 tape recorders (each with 10mintues capacity) |
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