ISRO's SSLV-D3 successfully launches EOS-08 and passenger satellites

Sriharikota, (Andhra Pradesh): In yet another successful mission, the Indian Space Research Organisation (ISRO) launched the latest Earth Observation Satellite EOS-8 and a passenger satellite using the Small Satellite Launch Vehicle (SSLV) from the Spaceport of Sriharikota on Friday morning.

After a short and smooth 6.5 hr countdown that began at 0247 hrs, SSLV-D3, the third and final developmental flight carrying the 175.5 kg EOS-08 and SR-0 DEMOSAT took off majestically from the First Launch Pad as scheduled at 0917 hrs from the SHAR Range.

ISRO said EOS-08 marks a significant advancement as it carries a host of new technology developments in satellite mainframe systems like an Integrated Avionics system, known as the Communication, Baseband, Storage, and Positioning (CBSP) Package, which combines multiple functions into a single, efficient unit.

This system is designed with cold redundant systems using commercial off-the-shelf (COTS) components and evaluation boards, supporting up to 400 Gb of data storage.

Additionally, the satellite includes a structural panel embedded with PCB, an embedded battery, a Micro-DGA (Dual Gimbal Antenna), an M-PAA (Phased Array Antenna), and a flexible solar panel, each serving as key components for onboard technology demonstration.

The satellite employs a miniaturized design in its Antenna Pointing Mechanisms, capable ofachieving a rotational speed of 6 degrees per second and maintaining a pointing accuracy of Plus or Minus 1 degree.

The miniaturized phased array antenna further enhances communication capabilities, while the flexible solar panel incorporates a foldable solar panel substrate, GFRP tube, and CFRP honeycomb rigid end panel, offering improved power generation and structural integrity.

A pyrolytic graphite sheet diffuser plate, known for its high thermal conductivity of 350 W/mK, reduces mass and finds application in various satellite functions.

Furthermore, the EOS-08 mission adopts a new method of integrating housekeeping panels using a hinge-based fixture, significantly reducing the duration of the Assembly, Integration, and Testing (AIT) phase.

Incorporating additional novel schemes, the EOS-08 mission improves satellite technology through X-band data transmission, utilizing pulse shaping and Frequency Compensated Modulation (FCM) for X-Band data transmitters.

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.

The mission's indigenization effort is evident in its solar cell fabrication processes and the use of a Nano-Star Sensor for Microsat Applications. Additionally, the inertial system benefits from reaction wheel isolators that attenuate vibrations and a single antenna interface is utilized for TTC and SPS applications.

Thermal management is enhanced using materials such as AFE BGA, Kintex FPGA, Germanium Black Kapton, and STAMET (Si-Al Alloy) Black Kapton to handle the thermal properties of COTS components.

The mission also incorporates an auto-launch pad initialization feature, further demonstrating its commitment to innovative mission management.