characteristics, and there is a continuing developmental work (e.g. propulsion systems) to enhance the capabilities of nanosatellite and picosatellite systems. 2 Comparison of satellite system characteristics Satellite system Traditional satellite systems Typical nanosatellite and characteristic picosatellite systems Spectral usage The frequency band and transmission parameters of these systems are subject to the ITU Radio Regulations Transmission Low to high systems Low transmission power, but not necessarily low power spectral density (PSD) Transmission A few kbps to Gbps depending on A few kbps to a few Mbps, lower data rates, modulation the service, usually bandwidth rates, typically optimized for power schemes efficient (Quaternary Phase Shift efficiency (e.g. Frequency Keying or higher order) Modulation/Frequency Shift Keying) considerations and without coding Antenna Many antenna types. Typically only 1 or 2 active antennas emission directionality directional antennas are often per band, often omnidirectional (for used, especially for critical example due to lack of attitude control operations (e.g. satellite and/or antenna pointing mechanisms) recovery). Sometimes antennas are used Transmission Planned with known associated earth station(s) or service area(s) control (switching on and off) TABLE 2 (end) Satellite system Traditional satellite systems Typical nanosatellite and characteristic picosatellite systems Type of orbit All types Mainly low orbit (LEO) Launch Established years in advance; Mostly opportunistic; based on arrangements however, some contractual available space on scheduled launch adjustments are fairly common vehicles. Possibility for dedicated for commercial satellites launches Dedicated launches provide Non-dedicated launches (e.g. greater control over the range of opportunistic secondary payloads) may orbital parameters in mission require consideration of a greater range planning of potential orbital parameters in considerations mission planning Station keeping Usually, on board propulsion to Usually, no on propulsion or maintain orbital parameters limited manoeuvring capability. Some of these missions and future missions will have propulsion systems
characteristics, and there is a continuing developmental work (e.g. propulsion systems) to enhance the capabilities of nanosatellite and picosatellite systems. 2 Comparison of satellite system characteristics Satellite system characteristic Traditional satellite systems Typical nanosatellite and picosatellite systems emission considerations Spectral usage The frequency band and transmission parameters of these systems are subject to the ITU Radio Regulations Transmission Low to high systems Low transmission power, but not necessarily low power spectral density (PSD) Transmission rates, modulation schemes A few kbps to Gbps depending on the service, usually bandwidth efficient (Quaternary Phase Shift Keying or higher order) A few kbps to a few Mbps, lower data rates, typically optimized for power efficiency (e.g. Frequency Modulation/Frequency Shift Keying) and without coding Antenna directionality Many antenna types. antennas are often used, especially for critical operations (e.g. satellite recovery). Sometimes directional antennas are used Typically only 1 or 2 active antennas per band, often omnidirectional (for example due to lack of attitude control and/or antenna pointing mechanisms) Transmission control (switching on and off) Planned with known associated earth station(s) or service area(s) TABLE 2 (end) Satellite system characteristic Traditional satellite systems Typical nanosatellite and picosatellite systems considerations Type of orbit All types Mainly low orbit (LEO) Launch arrangements Established years in advance; however, some contractual adjustments are fairly common for commercial satellites Mostly opportunistic; based on available space on scheduled launch vehicles. Possibility for dedicated launches Dedicated launches provide greater control over the range of orbital parameters in mission planning Non-dedicated launches (e.g. opportunistic secondary payloads) may require consideration of a greater range of potential orbital parameters in mission planning Station keeping Usually, on board propulsion to maintain orbital parameters Usually, no on propulsion or limited manoeuvring capability. Some of these missions and future missions will have propulsion systems
R-REP-SA.2312-2014-MSW-E.docx