about link budget - RF Cafe Forums

 Post subject: about link budget

Posted: Fri Dec 01, 2006 10:32 pm 

i tried to slove this. but i couldent. can anyone?

the uplink of a satellite system has the following parameters.
earth station saturated power output 32dBW
earth station branching losses 2.83dB
earth station back off losses 4.4dB
earth station antenn gain 62dB
atmospheric losses 0.6dB
free space path losses 205.3dB
satellite receiver G/Te ratio 5.1dB/K
bit rate 120Mbits/s

the modulation scheme is 8psk and the satellite receiver noise bandwidth is equil to the minimum noise bandwidth, calculate the

EIRP of the earth station
carrier power density at the satellite antenna.
carrier to noise power density at the satellite
energy per bit density ratio
wideband carrier to noise ratio

U are doing a great help for me. coz i dont have anyone to ask about this. bye.
thx

 Post subject: ?????????/

Posted: Fri Dec 01, 2006 11:23 pm 

hi
i dont want the whole calculation.
please anyone can send the formulas.
and what is the important of the modulation scheme. 8psk?
thx

 Post subject:

Posted: Mon Dec 04, 2006 7:23 am 

Hi
Try the following page

http://www.satsig.net/linkbugt.htm

It is an on-line calculator. Enter your data and see if it gives a useful result.

You can find Satellite Link Budget freeware using those 3 search words in Google.

8 psk is just the modulation encoding that enables the bandwidth for a certain information rate on the serial datastream to be calculated. It effects the Bit Error Ratio for a particular value of Carrier Power/Noise Power and convolutional coding/forward error correction. Ignore it for now.

Any problems, just let us know.

 Post subject:

Posted: Thu Jan 11, 2007 2:20 pm 

hi,

some examples can be found here; http://www.producon.com/sm7ovk/linkbudget.html

it's for VHF but you could check your other calculations accordingly.

Regards
Jens