Satelltie Antennas

Microwaves And Satellite Communication

Saturday, February 20th, 2010

Author: Kyle Newton

Micro is a unit for measurement of length. As the name suggests microwaves are the portion of the electromagnetic spectrum where the wavelength falls between about one millimeter and thirty centimeters that is micrometers.

Frequency of microwave bands extends from about one gigahertz to three hundred gigahertz and is useful for short range, high reliability radio and television links. Systems which use microwave frequencies are radar, mobile radio, satellite communications, terrestrial line of sight and troposphere links.

Satellite Antennas

Thursday, November 5th, 2009

Antennas are essential components of a satellite system. They are located aboard the satellites and as part of the ground equipment suites. The signal transmitted from a ground terminal antenna up to a satellite is called an uplink, and the transmission from a satellite to a ground terminal antenna is called a downlink. The frequencies of the uplink and downlink are never the same. The uplink frequency is normally higher. The reason for this, it is easier to generate radio frequency power on the ground rather than aboard the satellite where weight and power are limited. For a large dish reflector antenna on the ground, using the higher frequency (which has shorter wavelength) for the uplink will maximize the signal power that is transmitted to the satellite. This is important because the satellite, in comparison, will be more disadvantaged in its ability to strongly receive and transmit signals. Again, the larger ground antenna will have the advantage to more strongly collect the weaker, lower frequency downlink signals transmitted by the satellite.

Satellite Dish

Monday, February 9th, 2009

The satellite dish is a satellite antenna that is parabolic in shape and receives and re-transmits the signals from and to different locations, mostly the satellite. The satellite dish is nothing but a microwave antenna that is available in different sizes and shapes.