project on satellite tracking

[hejas.sp]

hi
i am doing a project on satellite tracking.can anyone help me out with some information or papers regarding this. As the whole thing is new to me ,can someone link me with few existing projects and sites about the same.Many thanx in advance

 

[chuckey]

I got involved with satellite tracking about twenty years ago. All satellites radiate a pilot transmitter, which is what the position controller "looks at" . The position of the satellite can be predicted with enormous accuracy, the controller is pre-programmed with the parametres and for its first 48 hours of life on any satellite, the controller is "filling in " the various constants in the mathematical model. British Telecomms has 14 different terms in its algorithm (perhaps based on the 1960s Telstar/Goonhilly experience), most commercial units have only 8 or 9. So it is obvious the controller must have an accurate clock/calender else it cannot predict where the satellite will be drifting off to as the dish pointing accuracy is in the order of .01 degrees. One clapped out Russian ex-military satellite we were using, required the dish to be moved every few minutes, "proper" satellites needed correction less then once a day.
Frank

 

[kabeer02]

Hmm, very interesting i always like to here about satellite tracking systems and that is what i intend to study but along the line i become an electronics engineer,i will also like to have any material,tutorials,or e book may be it will help me to start some where.....

 

[tpetar]

hi
i am doing a project on satellite tracking.can anyone help me out with some information or papers regarding this. As the whole thing is new to me ,can someone link me with few existing projects and sites about the same.Many thanx in advance

What kind of satellite tracking you have in mind? Do you have your own personal satellite in Earth orbit? :smile:

Maybe you have in mind GPS tracking?

 

[jiripolivka]

What kind of satellite tracking you have in mind? Do you have your own personal satellite in Earth orbit? :smile:

Maybe you have in mind GPS tracking?

There are two basic systems for satellite tracking.
One is often named "Step-Track". The system measures an averaged voltage from the receiver tuned to the satellite beacon signal. To a programmed time interval, it moves the receiving antenna in small steps, in azimuth, and measures the receiver output voltage. If it falls, it returns the antenna position back. If it grows, it makes one more step. After several runs it stops close to a maximum.
Then it turns the elevation in a similar way. After several optimizations, it waits to another run

The other system utilizes a special device in the antenna primary radiator which feeds two or four receivers. The device allows to point the antenna so the receivers generate equal outputs. If the balance is broken, the antenna is moved to return to the optimum pointing. The device splits the antenna radiation pattern so instead of the single pencil beam it forms a set of four peaks, each feeding its receiver channel. Other devices utilize orthopolar outputs as the orthopolar radiation pattern of an antenna has a sharp deep minimum when antenna points to a satellite.

All tracking systems suffer from weather effects, mainly rain, in frequency bands above ~10 GHz. The best treatment is to switch the tracking system off during a rain as after the satellite signal is lost by antenna searching for its maximum during rain loss, it is tricky to get it back.

 

[chuckey]

"All tracking systems suffer from weather effects, mainly rain, in frequency bands above ~10 GHz. The best treatment is to switch the tracking system off during a rain as after the satellite signal is lost by antenna searching for its maximum during rain loss, it is tricky to get it back." if you are operating an uplink service, your customers would get upset if you lost the satellite!!! :-(
Frank