Declination is a coordinate system that uses Latitude that is then projected on large arbitrary radius measurements around the Earth that rotate on the same axis. Declination’s main purpose is to locate a specific object or point in the sky. It is measured in a value of degrees north and south of the celestial equator. These values are positive if north of the celestial equator, zeroed if equal to the celestial equator, and negative in the south. For example, the following values are true for declination positions from the celestial Read More

S band is a frequency range from approximately 2 to 4 GHz. S band is used for Digital Audio Radio Satellite (DARS) satellite radio systems such as Sirius XM Satellite Radio.  Sirius XM uses frequencies between 2,320.00 and 2,332.50 MHz, and also between 2,332.50 and 2,345.00 MHz. S band is also used by many weather, communications, and intelligence satellites.  Most of these satellites transmit using CW, usually with sidebands.  PSK with a sub-carrier is a less popular option. A portion of the S band from 2.4 to 2.4835 Ghz is Read More

Uplink refers to a transmission of data in which data flows from a ground-based transmitter to an orbital satellite receiver. Uplink is used to send data to a satellite in Earth’s orbit in order to make changes to the way the satellite functions or simply redirect data to another ground-based receiver. Uplink is used in every application that involves the use of an orbital satellite and is a necessary component of all satellite-based telecommunications systems. Like downlink, uplink depends on the use of C Band, Ku Band, and Ka Band Read More

An LNB (Low Noise Block aka LNC- Low Noise Converter) is used for communications (broadcast) satellite reception. The LNB is usually affixed either in or on the satellite dish. The LNB’s purpose is to utilize the super heterodyne effect and amplify and convert a wide block (band) of frequencies. This helps compensate the signal loss associated with typical coaxial cable at relatively high frequencies. The term ‘low noise’ relates to the quality of the 1st stage input amplifier transistor, measured in either called Noise Temperature units, Noise Figure units, or Read More

TV-GPS is a technology from Rosum Corporation of California. Basically, it is a GPS tracking technology that makes use of television broadcasting signals to intensify or strengthen GPS signals. It is slated for use in urban areas where most people own a television (so the TV broadcasting signals are extremely strong) and where the regular GPS monitoring or tracking is rendered ineffectual because of great interference from electromagnetic noise and obstruction from concrete skyscrapers. Components of a TV-GPS System A TV-GPS system needs a device with a Rosum TV Measurement Read More

MCPC stands for Multiple Channel Per Carrier. MCPC is a form of satellite transmission where each carrier is utilized to transmit multiple channels. MCPC transmits multiple video or audio channels on one carrier by utilizing Time Division Multiplexing (TDM). The alternative to MCPC is SCPC (Single Channel Per Carrier). MCPC is used much more than SCPC because it makes much more efficient use of expensive satellite bandwidth.

Elevation refers to the varying heights of objects on, and around, the Earth. Elevation on Earth is usually used to measure the difference in height of land masses in comparison to Sea Level. Elevation in Earth’s orbit is used to measure the difference in height of satellites in comparison to the Earth’s horizon from any given point. In the latter form, elevation is a critical factor in properly configuring a satellite antenna.   How Elevation Works Elevation, in terms of satellites, is measured in degrees and depends on the horizon Read More

An IFL, or Interfacility Link, is a cable system that is used in facilities to connect an outdoor unit and an indoor unit. An outdoor unit refers to the satellite receiver or coaxial cable that connects a service provider to a company while an indoor unit refers to the coaxial cables, routers, or transmitters inside the building. IFLs are used to minimize the amount of interference received on the transmission by rerouting the signal through a combination of different technologies.   How IFL Works In a typical direct broadcast satellite Read More

8PSK (8 Phase Shift Keying) is a phase modulation algorithm. Phase modulation is a version of frequency modulation where the phase of the carrier wave is modulated to encode bits of digital information in each phase change. The “PSK” in 8PSK refers to the use of Phased Shift Keying. Phased Shift Keying is a form of phase modulation which is accomplished by the use of a discrete number of states. 8PSK refers to PSK with 8 sates. With half that number of states, you will have QPSK. With twice the Read More

A “broad beam” in satellite-based telemetry is a beam of radio waves that is focused on a large area of the Earth’s surface. Broad beams are commonly used to transmit data from an orbital satellite to a large number of ground-based receivers simultaneously. Broad beams are also used in satellite-based radar and GPS in order to view large areas of the Earth’s surface at one time. Broad beams typically require more power than spot beams, but provide a much wider coverage area and generally transmit the same amount of data. Read More