The Low Gain Antenna (LGA) is an antenna with a broad radiowave beam width. This very wide beam allows for a more reliable signal that is best used in mountainous regions, where the signal will propagate reasonably well regardless of terrain. The mountains become the equivalent of rocks in a stream, surrounded by the flowing waves. Low gain antennas are often used in spacecraft as a backup to the High Gain Antenna, which transmits a much narrower beam and is therefore susceptible to loss of signal. A yagi antenna Most simply, an antenna is an electronic component designed to send or receive radio waves. ... Jump to: navigation, search The High Gain Antenna (HGA) is an antenna with a focused, narrow radiowave beam width. ...
An antenna without gain (0db) radiates energy in all directions equally and antenna with gain redirects or concentrates energy in a certain direction and the gain performance is measured in the direction of the energy concentration.
It is possible to calculate the effect of antenna placement by measuring the signal level at the phone location and the signal level at the proposed external antenna position and subtracting the loss of a known length of cable with a known loss per foot.
Antenna co-ax cable is the critical component in antenna system performance that is almost always overlooked and is most likely to be of poor or medium grade when an antenna purchase is made.
Scientific instruments to measure fields and particles, together with the main antenna, the power supply, the propulsion module, most of the computers and control electronics, are mounted on the spinning section.
The instruments include magnetometer sensors, mounted on an 11-meter (36-foot) boom to minimize interference from the spacecraft; a plasma instrument detecting low-energy charged particles and a plasma-wave detector to study waves generated by the particles; a high-energy particle detector; and a detector of cosmic and Jovian dust.
Fortunately Galileo had an additional low-gain antenna that was capable of transmitting information back to Earth, but the low-gain antenna's bandwidth was significantly less than the high-gain antenna's would have been; the high-gain antenna was to have transmitted at 134 kilobits per second whereas the low-gain antenna's bandwidth was only 160 bits per second.
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