Landsat TM Image Data Archived in China Remote Sensing Satellite Ground Station

Landsat 5 was launched on March 1, 1984, carrying a seven-band TM sensor, and
still operates properly at present. The satellite takes a sun-synchronized
orbit with 705km altitude and 98.22 deg. inclination.

A TM scene covers 185km by 170km earth surface approximately, with 30m ground
resolution for band 1,2,3,4,5,7 and 120m for band6. For a particular place, the
revisit cycle of the satellite is 16 days.

Chaina Remote Sensing Satellite Ground Station(CRSGS) was inaugurated and
become operational in Dec. 1986. Up to now it is the most important source of
remote sensing satellite data in China for earth resouce exploration and
environment monitoring.

CRSGS has provided a large amount of satellite remote sensing products to more
than 400 users, domestic and abroad. Applications of TM images have resulted
in great economic and social benefits in a wide range of areas of national
economy: resource survey and utilization, environment monitoring, geographic
cartography, minerarl exploration, disaster detecting and assessing, etc.

TM data received by CRSGS since 1986 have been archived. Through a Catalogue
Archive and Browse System(CABS), users can retrieve useful information about
data of interests. A image(or a group of images) could be searched according
to date, location(latitude-longitude or path-row), and quality, etc. Text
catalogue is available for all TM data in the archival. In addition to text
contents, sub-sampled browse images are available for data acquired after
Apr.,1994.

The major products of CRSGS are TM data on CCTs, floppy disks and imagery on
films or papaer prints. Products fall into two categories with respect to
processing methods.
1. Standard processing
includes systematic correction, precision correction, and geocoding, etc.
2.Special product(user dependent)
includes multi-scene mosaicking, image classification, user defined annotation
or administrative boundary adding, special juts enhancement, etc.

陆地卫星5号（Landsat 5）于1984年3月1日发射，搭载7波段专题制图仪（Thematic Mapper, TM）传感器，目前仍处于正常运行状态。该卫星采用轨道高度705千米、倾角98.22度的太阳同步轨道。

单幅TM影像覆盖约185千米×170千米的地表范围，其中波段1、2、3、4、5、7的地面分辨率为30米，波段6的地面分辨率为120米。针对特定区域，该卫星的重访周期为16天。

中国遥感卫星地面站（China Remote Sensing Satellite Ground Station, CRSGS）于1986年12月建成并投入运行，是目前国内开展地球资源勘探与环境监测的核心遥感卫星数据来源。

中国遥感卫星地面站已为国内外400余家用户提供了大量卫星遥感产品。TM影像的应用在国民经济诸多领域产生了显著的经济与社会效益，涵盖资源调查与利用、环境监测、地理制图、矿产勘探、灾害监测与评估等多个方向。

自1986年起，中国遥感卫星地面站接收的TM数据已完成归档存储。用户可通过目录归档与浏览系统（Catalogue Archive and Browse System, CABS）检索所需的数据信息。检索可依据日期、位置（经纬度或轨道条带号）、数据质量等条件进行。归档的所有TM数据均提供文本目录；1994年4月之后获取的数据，除文本内容外，还可获取降采样浏览影像。

中国遥感卫星地面站的主要产品包括存储于计算机兼容磁带（Computer Compatible Tape, CCT）上的TM数据、胶片或纸质印刷的影像产品。依据处理方式，产品可分为两类：
1. 标准处理产品：包含系统校正、精校正与地理编码等处理流程；
2. 定制产品（面向用户需求）：包含多景影像镶嵌、影像分类、用户自定义注记或添加行政边界、专项增强处理等。