How does a satellite work?

Answer 1

A satellite system consist of four parts.
1. the sending unit-this can be a TV station for example. It is the place where the signal is made.
2. the signal is sent to the satellite -they are many thousands of miles up in space.
3. the satellite then sends the signal to the individual satellite dishes on peoples houses. Each house has a satellite receiver which has a special code that tells the satellite it is allowed to receive the signal. The satellite signal is sent to everyone everywhere, but it can not be received unless that satellite dish has the proper code. It's sorta like encrypted stuff on the computer. Gibberish unless you have the code to allow you to decrypt whatever it is that has been encrypted. Each satellite receiver has a card-it looks like a credit card-that is plugged into the satellite receiver. That card says that that receiver can receive the signal. the card will not work on another receiver, it will only work on that receiver.

Answer 2

Please clarify.
Do you mean how come it doesn't fall down?

Or how does it send signals to earth, as in satellites used for communication, for radio, for GPS, for the Hubble?

A low satellite is moving slower than a high satellite. When it goes too slow, it falls down. if it's going too fast, it escapes Earth altogether and can end up in outer space between planets but is still in orbit around the Sun. Faster still and it can leave the Solar System. It's all about gravity and speed. The gravity causes the object to go down instead of straight, so it's like the string on a yo-yo keeping it from flying off in a straight line.

Think of standing on the Equator. It takes 24 hours to go 25000 miles. A low satellite goes around in about 2 hours, higher up but still about 25000 miles. So that tells you the speed. You have to be about 50 miles up to get out of the atmosphere - you can't orbit at 10 feet off the ground or even one mile up. If there were no air or mountains, you could.

The faster it goes, the longer the "string", the higher the satellite is. When it's high enough up, it takes a whole day to go around, so it can stay in the same spot in our sky if it's over the Equator. And that's the ones they use for TV signals, so your DirectTV dish can point at it.

The study of how satellites, moons, planets, and other objects move through space is called Orbital Mechanics.

Answer 3

I don't think it would do somuch differs with that of conventional radar, firstly a the setelite had been program to pick up certaintly carrier frequency width,say from 10 MHz to 200 MHz then it would signal back to Earth at the same freq with its carrier frq sets, say at 10.13 MHZ then the radar would receives any signal this carrier freq and spread it out, say to TV and Radio, on this carrier freq, any signal it carry, say Audio and Video. Regardless, there other signal via other Signal nearby,say at 10.20 MHz, 10.25 MHz,10.30MHZ and so on, being 'catch-on' by the same radar on the ground,to change it 'content' you would jaust change the 'tuning' dial on your radio or TV. But on a FIX system, such as Airport,Seaport and the like,which requires a fix-point,the above option on changing could be prohibited.