Defence Satellites and Reconnaissance Systems is part of Defence Technology. Below are notes on 1 sub-topics, followed by practice MCQs from State PSC and UPSC papers (coming soon).
Unmanned Aerial Vehicles (UAVs) and High-Altitude Pseudo Satellites (HAPS) for Reconnaissance
- UAVs (Unmanned Aerial Vehicles): Remotely piloted or autonomously programmed aircraft primarily used for Intelligence, Surveillance, Reconnaissance (ISR), targeting, and combat missions.
- HAPS (High-Altitude Pseudo Satellites): Aircraft (e.g., gliders, airships, fixed-wing platforms) designed to operate in the stratosphere (typically 17-22 km altitude) for extended periods (weeks to months).
Secure
Communication
Technologies
(Cryptography, Anti-jamming, Stealth)
- Secure Communication Technologies ensure data integrity, confidentiality, authentication, and non-repudiation in defence systems.
- Core technologies include Cryptography, Anti-jamming, and Stealth.
- Cryptography: Techniques for secure communication using codes, ensuring privacy and authenticity.
- Cryptographic methods include Symmetric (e.g., AES) and Asymmetric (e.g., RSA, ECC) key algorithms.
- Anti-jamming: Countermeasures against intentional or unintentional interference with communication signals.
- Anti-jamming techniques include Frequency Hopping Spread Spectrum (FHSS), Direct Sequence Spread Spectrum (DSSS), adaptive antenna arrays, and error correction codes.
- Stealth: Technologies designed to reduce the detectability of platforms or signals by radar, infrared, sonar, or visual means.
- Stealth methods involve Radar-Absorbent Material (RAM), aerodynamic shaping, infrared suppression, and Low Probability of Intercept (LPI) communication techniques.
- SANCHAR: An 'end-to-end secure mobile ecosystem' developed by the Indian Army to provide secure communication for its personnel.
- HAPS Operational Zone: Positioned above commercial air traffic and most weather phenomena, but below Low Earth Orbit (LEO) satellites.
- HAPS Advantages for Reconnaissance: Offer persistent regional presence, lower latency imagery than satellites, more flexible deployment/recovery, and longer endurance than conventional UAVs.
- Reconnaissance Role: Both UAVs and HAPS provide critical ISR capabilities, offering real-time or near real-time data collection over specific areas for defence applications.
- August 2016 Data Leak: Sensitive information leaked in August 2016 concerned the combat capabilities of India's Scorpene-class