PRELIMINARY RESEARCH ON POSITION ACCURACY OF CARTOSAT-1
Liping Zhao a ’ *, Fengde Liu a , Wei Wang b , Jian Li a
Chinese Academy of Surveying and Mapping, Beijing, 100039 zhaolpwww@sina.com liufd6879@yahoo.com.cn
lij ianbj @sina. com
b National Disaster Reduction Center of China, Beijing, 100053 wangwei@ndrcc.gov.cn
Commission I, SS-11
KEY WORDS: Mapping Satellite; CARTOSAT-1; Rational Function Model; Position Accuracy
ABSTRACT:
In this paper, the development of Indian Remote Sensing Satellite Serials is reviewed, the specifications of CARTOSAT-1 satellite
platform and Sensor is introduced and compared with IKONOS^ SPOT5 HRS. The positioning algorithm using Rational Function
Model (RFM Model) of CARTOSAT-1 is described in detail. Experimentation is carried out using stereo pair of Beijing hilly area.
The results show that with high accurate and well-distributed Ground Control Points (GCPs) the plane and elevation accuracy of
CARTOSAT-1 imagery could reach 5-meter and meet the mapping requirements of 1:50,000 national topographic map.
1. INTRODUCTION
From the first satellite launched in 1975, India has formed a
relatively integrated space technology development and
application system, which includes earth observation,
astronomy, communication, broadcasting, remote sensing, and
reconnaissance satellite series.
Indian Remote Sensing satellites (IRS) are a series of Earth
Observation satellites, mostly built, launched and maintained by
Indian Space Research Organisation of India as part of the
Indian space program. IRS series include OceanSat, CartoSat,
ResourceSat. Some of the satellites have alternate designations
based on the launch number and vehicle (P series for PSLV).
The first generation satellite IRS-1A and IB were designed,
developed and launched successfully during 1988 and 1991
with multi-spectral cameras with spatial resolution of 72.5 m
and 36 m. respectively. Subsequently, the second generation
remote sensing satellites IRS-1C and ID with improved spatial
resolutions of 70 m in multi-spectral and 5.8 m. in
Panchromatic bands and a wide field sensor with 188m
resolution and 800 Km. swath, have been developed and
successfully launched in 1995 and 1997 respectively. These
satellites have become the principal components in the National
Natural Resource Management System and the data was used in
various applications, viz., agriculture and soil, land form and
land use studies, water resource, forestry, drought and flood
monitoring, cartography, town planning and coastal zone
monitoring. Especially IRS-1 C/D data has been used for
cartographic and town planning application up to 1:10,000 scale.
These satellites also provide stereo pairs of imageries to get
height information to an accuracy of approximately 10
meters(Smith, 1987b; Moons, 1997).
CARTOSAT-1 was launched successfully on 5 May 2005,
which reached international excellence and indicated new stage
of India remote sensing technology. The satellite and camera
specification is listed below.
Satellite Features of CARTOSAT-1:
• Orbit: Circular Polar Sun Synchronous
• Orbit height: 618 km
• Orbit inclination : 98.87 deg
• Orbit period : 97 min
• Number of Orbits per day : 14
• Local Time of Equator Crossing: 10.30 AM
• Repetivity : 126 days
• Revisit: 5 days
• Lift-off Mass : 1560 kg
• Attitude and Orbit Control : 3-axis stabilised
using Reaction Wheels, Magnetic Torquers and
Hydrazine Thrusters
• Electrical Power : 1100 W using 5 sq m Solar
Array Two 24 Ah Ni-Cd batteries
• Mission Life ; 5 years
• Payloads : Two PAN Cameras one fore-
mounted with a tilt of +26 deg and the other
Aft-mounted with a tilt of -5 deg from the yaw
axis Camera Specifications of CARTOSAT-1:
• Instantaneous Geometric ; < 2.5 m Field of
View (IGFOV)
• Swath : 30 km
• Spectral Band : 0.50-0.85 micron
• Data rate : 105 Mbps for each camera
• Solid State Recorder: 120 GB capacity for
image data storage
Once commissioned, CARTOSAT-1 will give further fillip to
remote sensing services by providing imagery with
improved spatial resolution. Two cameras working at 26
