2007-03-22 22:49:21 · 3 answers · asked by sumit 1 in Science & Mathematics ➔ Engineering
The downlink frequency, sent from the satellite to an earth based station is greater because it requires less energy to transmit and has higher bandwidth which allows the satelite to be fitted with smaller and fewer transmitters. The transmitter requires the greater power consumption than a receiver.
2007-03-22 23:00:29 · answer #1 · answered by Jim M 2 · 0⤊ 0⤋
There are always 2 bands, the uplink and the downlink. It is necessary because they are both transmitting all of the time. They must be separated in frequency because they will interfere with each other if very close together.
Downlink frequency band in mobile phones is higher because the higher the frequency, the more susceptable to interference. The mobile phone is a very low-power device and it needs every bit of advantage in transmission. Putting it on the lower frequency increases its ability to communicate. The downlink transmission from the cell tower to the mobile phone is on a higher frequency since it has considerably high power output. This higher power negates the effects of the higher frequency.
The previous answer did not address your question. I hope this provides what you needed.
2007-03-22 23:06:13 · answer #2 · answered by bobinbelen 2 · 1⤊ 0⤋
It is called an asychronous line. Most of the time, the device is receiving much more content than it is sending. This is the same for most DSL and cable modems.
The reason this is done is because bandwidth is finite and it is best to divide it to make it more efficient.
Think of bridges or highways during rush hour. Often, more lanes are reserved in the direction of high demand.
2007-03-22 22:58:14 · answer #3 · answered by Matthew P 4 · 1⤊ 2⤋