Jargon Buster

Antenna (dish): A device that concentrates a beam of electromagnetic waves so as to send or receive signals. 

Aperture: Effective cross-section area of the antenna. A larger aperture means a stronger signal is sent or received. 

Backup Network: Alternative network for contingency should main network fail. 

Bandwidth: A leased resource from the satellite operator measured in Hertz, the larger the Bandwidth the more data can pass through it. 

Bit Rate: Speed of which the bits are transmitted, express as bits per second (bps). 

Broadcasting: A single transmission received by all remote stations, for example a TV broadcast. 

C-band: The frequency band in the 4 – 6 GHz range 

Channel: A communications connection between two points. This may be “Simplex” (One Way) or “Duplex” (Both Ways). 

Coverage: See footprint 

DAMA: Demand Assigned Multiple Access, allows many users to share common bandwidth. 

Double Hop: Communication from one satellite remote to another satellite remote via a HUB, the result is a ‘double hop’ over the satellite adding delay to signal. 

Downlink: The retransmission by a satellite of an Uplinked signal. 

E1: A common communications channel carrying voice traffic used by telephone companies. 

Earth Station: A satellite antenna (technically >3.6M) and it’s Radio Equipment 

FEC: Forward Error Correction, applied to the signal so that receivers can correct any errors. 

Feed: A device mounted at the correct point of the antenna so that it gathers signal reflected from the dish, reverse is true for transmit. 

Footprint: Area of the Earth where reception to and from the satellite is possible 

Frame Relay: A switching network protocol used by large data networks. 

GEO: Geostationary Earth Orbit 

Geostationary: The position of a satellite from Earth where it’s speed matches the Earths rotation therefore appearing as a fixed point in the sky. 

GUI: Graphical user Interface 

HPA: High Power Amplifier 

HTTP: Hyper Text Transfer Protocol, used for communication on the Internet. 

Hub: A central Satellite Earth Station capable of serving many clients/remotes. 

IDU: Indoor unit, such as modem located indoors. 

IP: Internet protocol, defines packets sent across the Internet. 

ITU: International Telecommunications Union, A United Nations body helping governments co-ordinate radio usage. 

Ka Band: 20-30 Ghz, not used significantly but this is the highest frequency satellite band in use today. 

Ku Band: 10-14 Ghz, a commonly used band for satellite communications networks. 

LAN: Local Area Network, A computer network covering a small area. 

LNB: Low Noise Block Down Converter , the receiver part of the Antenna system. 

Mesh Network: A type of network where each remote can communicate with any other remote in only one satellite hop. 

MF-TDMA: Multiple-Frequency Time Division Multiple-Access, A broadband method where remotes share allocated segments identified by both frequency and time. 

Modem: Modulator/Demodulator, converts the radio signals to/from digital signals. 

NCC: Network Control Center 

NMS: Network Management System, software used for the management and control of a network. 

NOC: Network Operations Center 

Packet: Data bits and control bits transmitted through a network as part of a larger message. 

QoS: Quality of Service, the guarantee of specific bandwidth/delay time of applications. 

Satellite: A object orbiting a larger one such as a Communications Satellite orbiting the Earth. 

SCADA: Supervisory Control and Data Acquisition, The process of monitoring and controlling devices used in engineering such a pipeline segments. 

Single Hop: Transmission through a satellite only once 

SLA: Service Level Agreement 

Space Segment: Portion of Satellite bandwidth assigned to end user/operator. 

TCP: Transmission Control Protocol, often combined with IP. 

TCP/IP: The combination of TCP and IP. 

TDMA: Time Division Multiple Access, The sharing of bandwidth between multiple users on a time slot basis. 

Throughput: The measurement of the volume of data through a channel in specified time. 

Transponder: A single uplink/Downlink amplifier of which a Satellite usually has many. 

VSAT: Very Small Aperture Terminal. A remote satellite antenna and Radio equipment (technically, <3.6m)