ISRO New Earth Observation Satellite EOS-08: A Technological Marvel in Earth Observation
The Indian Space Research Organisation (ISRO) is set to launch its latest Earth Observation Satellite, EOS-08, aboard the Small Satellite Launch Vehicle (SSLV)-D3. This mission represents a significant leap in satellite technology, featuring several key innovations and objectives designed to enhance ISRO’s capabilities in various fields such as disaster monitoring, environmental observation, and remote sensing.
A Leap in Satellite Technology
EOS-08 is built on the Microsat/IMS-1 bus and is equipped with three sophisticated payloads that highlight its advanced capabilities:
1. Electro Optical Infrared Payload (EOIR): This payload can capture images in the Mid-Wave IR (MIR) and Long-Wave IR (LWIR) bands during both day and night. Its applications include satellite-based surveillance, disaster monitoring, environmental monitoring, fire detection, volcanic activity observation, and monitoring of industrial and power plant disasters.
2. Global Navigation Satellite System-Reflectometry Payload (GNSS-R): This payload demonstrates the use of GNSS-R-based remote sensing for applications such as ocean surface wind analysis, soil moisture assessment, cryosphere studies over the Himalayan region, flood detection, and inland waterbody detection.
3. SiC UV Dosimeter: This instrument monitors UV irradiance at the viewport of the Crew Module in the Gaganyaan Mission and serves as a high-dose alarm sensor for gamma radiation.
Advanced Mainframe Systems and Innovations
EOS-08 incorporates significant advancements in satellite mainframe systems, particularly with the introduction of the Integrated Avionics system, known as the Communication, Baseband, Storage, and Positioning (CBSP) Package. This system integrates multiple functions into a single, efficient unit, featuring cold redundant systems using commercial off-the-shelf (COTS) components and evaluation boards, supporting up to 400 Gb of data storage.
Additional technological innovations include:
Pyrolytic Graphite Sheet Diffuser Plate: With high thermal conductivity (350 W/mK), this plate reduces mass and is used in various satellite functions.
Structural Panel Embedded with PCB: Enhances the integration of electronic components.
Embedded Battery: Improves power management and efficiency.
Micro-DGA (Dual Gimbal Antenna) and M-PAA (Phased Array Antenna): Enhances communication capabilities.
Flexible Solar Panel: Incorporates a foldable solar panel substrate, GFRP tube, and CFRP honeycomb rigid end panel, providing improved power generation and structural integrity.
Miniaturized Design and Advanced Materials
The satellite employs a miniaturized design in its Antenna Pointing Mechanisms, capable of achieving a rotational speed of 6 degrees per second and maintaining a pointing accuracy of ±1 degree. The miniaturized phased array antenna further enhances communication capabilities.
The flexible solar panel design offers significant improvements in power generation and structural integrity. The foldable solar panel substrate, GFRP tube, and CFRP honeycomb rigid end panel contribute to this advancement.
EOS-08 utilizes advanced materials for thermal management, including AFE BGA, Kintex FPGA, Germanium Black Kapton, and STAMET (Si-Al Alloy) Black Kapton, effectively managing the thermal properties of COTS components. A new method of integrating housekeeping panels using a hinge-based fixture significantly reduces the duration of the Assembly, Integration, and Testing (AIT) phase.
Innovative Data Transmission and Power Management
The EOS-08 mission incorporates additional novel schemes, such as X-band data transmission using pulse shaping and Frequency Compensated Modulation (FCM). The satellite’s battery management system employs SSTCR-based charging and bus regulation, sequentially including or excluding strings at a frequency of 6 Hz. The TM-TC system supports dual modes, including CDMA and Direct PSK, with miniaturized microstrip filters tailored for data and TM-TC applications.
Indigenization and Future Prospects
The mission also highlights ISRO’s indigenization efforts, evident in its solar cell fabrication processes and the use of a Nano-Star Sensor for Microsat Applications. The inertial system benefits from reaction wheel isolators that attenuate vibrations, and a single antenna interface is utilized for TTC and SPS applications.
EOS-08 stands as a testament to ISRO’s commitment to advancing satellite technology. From its sophisticated payloads to its innovative mainframe systems, the satellite is poised to provide valuable data for a range of applications. As ISRO continues to push the boundaries of space technology, missions like EOS-08 pave the way for future advancements and operational capabilities, ensuring that India remains at the forefront of space exploration and satellite technology.
