Useful links to elsewhere on this SATSIG web site:
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System Noise Temperature

Satellite Link Budget

Antenna gain

Explanation of satellite links

Satellite mobile phone link budget - return link from mobile to hub

Europe to Africa - Satellite internet broadband outlink

Africa to Europe - Satellite internet TDMA return link

VSAT information

SCPC 8kbit/s mesh network satellite link budget for 1.8m antennas

Digital TV - MPEG satellite link budget

Line of sight link radio budget - one way - single hop

Back to general purpose link budget calculator

Link Budget for satellite data broadcasting / distribution.

The information comprises 128kbit/s data.  1/2 rate Viterbi FEC is used.
To be sent to 0.9m diameter antennas.  Bandwidth is 250 kHz,

Transponder parameters EIRP=50 dBW, G/T=+5 dBK,  PFDsat = -80 dBW/m^2 ( say Eutelsat W2 )
Assume multi-carrier operating point 7 dB input and 4.5 dB output back off.

Uplink Satellite PFDsat = -80 dBW/m^2
Operating transponder PFD = -80 - 7 = -87 dBW/m^2
Operating PFD for this carrier = -87 -10log(250000 / 36000000) = -87 -21.6 = -108.6 dBW/m^2

Downlink  eirp = 50 - 4.5 - 10 log (250000 / 36000000) = 50 - 21.6 = 23.9 dBW

Amend white boxes as you wish. and click to any calculate button to obtain results in the green boxes. 

Uplink frequency GHz
Uplink antenna diameter m
Uplink antenna aperture efficiency e.g. 0.65
Uplink antenna transmit gain dBi
Uplink antenna, power at the feed W
Uplink EIRP dBW
Range (35778 - 41679) km
Uplink path loss dB
Uplink pfd at satellite dBW/m^2
Bandwidth Hz
Satellite uplink G/T dB/K
Uplink C/N dB

Downlink frequency GHz
Downlink receive antenna diameter m
Downlink receive antenna aperture efficiency e.g. 0.65
Downlink system noise temperature(antenna+LNA) K
Downlink receive antenna gain dBi
Downlink receive antenna G/T dB/K
Downlink satellite EIRP dBW
Downlink path loss dB
Downlink C/N dB

Uplink C/interference dB
Uplink C/N dB
Satellite C/intermod dB
Downlink C/N dB
Downlink C/interference dB
Total link C/N dB

Pre-calculated link budget with useful default parameters inserted (may be amended and recalculated)

Broadband satellite internet access service for US and South America

Broadband direct satellite internet access service for the Middle East

Satellite internet and satellite VoIP communications access for Africa

Australia broadband satellite access 

Satellite finder: Calculate dish aiming and pointing angles for any site

Any problems or comments please e-mail Eric Johnston
Copyright ? 1 Jan 1999 Satellite Signals Ltd All Rights Reserved
Last Revision: 3 Dec  2004,  9 Dec 2014.