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In November 1990, Primestar launched as the first North American direct-broadcast satellite service. Hughes's DirecTV, the first national high-powered upper K u -band satellite TV system, went online in 1994. The DirecTV system became the new delivery vehicle for USSB. In 1996, EchoStar 's Dish Network went online in the United States and has ...
As of July 2023, the website UCS Satellite Database lists 6,718 known satellites. Of these, 580 are listed in the database as being at GEO. The website provides a spreadsheet containing details of all the satellites, which can be downloaded. Listings are from west to east (decreasing longitude in the Western Hemisphere and increasing longitude ...
The C band is a designation by the Institute of Electrical and Electronics Engineers (IEEE) for a portion of the electromagnetic spectrum in the microwave range of frequencies ranging from 4.0 to 8.0 gigahertz (GHz). [ 1 ] However, the U.S. Federal Communications Commission C band proceeding and auction, designated 3.7–4.2 GHz as C band. [ 2 ]
Typical transponders each have a bandwidth between 27 and 50 MHz. Each geostationary C-band satellite needs to be spaced 2° longitude from the next satellite to avoid interference; for K u the spacing can be 1°. This means that there is an upper limit of 360/2 = 180 geostationary C-band satellites or 360/1 = 360 geostationary K u-band satellites.
For satellite Internet services in tropical areas with heavy rain, use of the C band (4/6 GHz) with a circular polarisation satellite is popular. [43] Satellite communications on the K a band (19/29 GHz) can use special techniques such as large rain margins, adaptive uplink power control and reduced bit rates during precipitation.
Similar to NASA's GOES satellites. The International Space Station (ISS) has long been used as a central satellite platform for other sensors, including Earth observation sensors. For example: LIS, SAGE III, TSIS-I, ECOSTRESS, GEDI, OCO-3, Diwata-1, and HICO. Radar altimeter used to monitor ocean surface height.
The World Teleport Association publishes lists of companies based on revenues from all customized communications sources and includes operators of teleports and satellite fleets. In order from largest to smallest, the Global Top 20 of 2021 were: [1] [2] SES (Luxembourg) Intelsat S.A. (Luxembourg) EchoStar Satellite Services (USA) Hughes Network ...
In the early days of home satellite dishes, the two types of service were low-power C-band service with large dishes 8 to 12 feet wide, and high-power Ku-band. [10] [11] In 1979, COMSAT announced a plan to allow viewers to receive programming directly from broadcast satellites, a concept called direct-broadcast satellite (DBS). This system ...