Satellite TV Technology Guide For Dummies

Satellite television is television delivered by the means of communications satellite. On Earth, the signal is received by a satellite dish and set-top receiver box. Satellite TV provides a wide range of channels and services.

Satellite television starts with a transmitting antenna located at an uplink facility. Uplink satellite dishes are very large, as much as 8.5 to 12.5 meters (27 to 41 feet) in diameter. The increased diameter results in more accurate aiming and increased signal strength at the satellite. The uplink dish is pointed toward a specific satellite and the uplinked signals are transmitted within a specific frequency range, so as to be received by one of the transponders tuned to that frequency range aboard that satellite. The transponder retransmits the signals back to Earth but at a different frequency band to avoid interference with the uplink signal. The retransmission typically happens in the C-band (4-8 GHz) or Ku-band (12-18 GHz) or sometimes both. The leg of the signal path from the satellite to the receiving Earth station is called the downlink.

The downlinked satellite signal, quite weak after traveling the great distance, is collected by a parabolic receiving dish, which reflects the weak signal to the dish's focal point. Mounted on brackets at the dish's focal point is a device called a feedhorn. This feedhorn is essentially the flared front-end of a section of waveguide that gathers the signals at or near the focal point and conducts them to a probe or pickup connected to a low-noise block downconverter or LNB. The LNB amplifies the relatively weak signals, filters the block of frequencies in which the satellite TV signals are transmitted, and converts the block of frequencies to a lower frequency range in the L-band range. Direct broadcast satellite dishes are fitted with an LNBF, which integrates the feedhorn with the LNB.

The satellite receiver set-top box demodulates and converts the signals to the desired form of output for television, audio, data, etc. Sometimes, the receiver includes the capability to unscramble or decrypt; the receiver is then called an Integrated receiver/decoder or IRD. The cable connecting the receiver to the LNBF or LNB must be of the low loss type RG-6, quad shield RG-6 or RG-11, etc. It cannot be standard RG-59.

The main advantage of satellite TV is that providers don't have to lay miles upon miles of cable to deliver television programs to you. They don't need uplink centers in every city which duplicates equipment. This saves you money because satellite TV is less expensive to maintain and up-grade, no re-laying of cable to up-grade services. If the primary uplink center has a problem, the secondary uplink center automatically takes over broadcasting. That's why satellite TV has a less than 1% outage rate. Satellite TV companies like Dish Network rate significantly higher in customer satisfaction than cable television companies.

Khalid M. Syed is a PPC marketer and SEO engineer. He owns websites like www.OzeVision.com and www.Deal4u.biz. He is currently promoting Dish Network offer actively.