Glossary
Definitions
7 definitions
DVB-S2 / DVB-S2X
Digital Video Broadcasting — Satellite Second Generation (DVB-S2) is the global standard for satellite broadband and broadcasting transmission; DVB-S2X is its 2014 extension delivering up to 51% higher spectral efficiency through finer modulation granularity, lower roll-off factors, and support for very low signal conditions.
Debris Mitigation
A set of design, operational, and disposal practices mandated by ITU guidelines and national regulators to minimise the creation of new orbital debris — including passivation of propulsion systems, controlled deorbit within 5 years of mission end, and avoiding manoeuvres that could cause fragmentation.
Deorbit
The controlled manoeuvre or natural process by which a satellite is removed from its operational orbit and caused to re-enter Earth's atmosphere, either through propulsive retro-burn (controlled deorbit) or gradual atmospheric drag (passive deorbit) — mandated within 5 years of end of life for LEO satellites by FCC rules (2022).
Digital Payload
A satellite communications payload where the signal processing — demodulation, switching, and re-modulation — is performed digitally onboard the spacecraft, enabling flexible beam routing, dynamic bandwidth allocation, and software-upgradable functionality unlike traditional analogue bent-pipe transponders.
Digital Twin (Space)
A virtual replica of a satellite, ground station, or entire constellation — continuously updated with real telemetry — used to simulate performance, predict failures, optimise operations, and test configuration changes before applying them to the physical system.
Direct-to-Device (D2D)
A satellite service architecture where standard, unmodified smartphones communicate directly with LEO satellites using standard cellular protocols (LTE/5G NTN), eliminating the need for specialised satellite handsets or additional hardware.
Dual-Use (Civil & Defense)
The characteristic of satellite systems and technologies that can serve both civilian commercial applications and military or government security requirements — a strategic attribute that enables government investment to subsidise commercial development and vice versa.