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EbNo measurement and EbNo Calculator

INSAT 4CR - Link Budget for remote DSNG site to the studio.

This page refers to a Ku band satellite new gathering vehicle (DSNG) uplink sending back video to the hub studio site.

Uplink frequency GHz
Uplink antenna diameter m
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
Transponder "gain" input PFD to output EIRP
Downlink frequency GHz
Downlink receive antenna diameter m
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

The satellite receive uplink G/T is  +5 dB/K

Uplink SFD = -90 dBW/m^2   single carrier. Note 4 dB input back off
Uplink PFD = - 90 - 4 multi carrier
Uplink PFD = -90 - 4 - 10log(1.5/36) for your uplink carrier
Uplink PFD = -107.8 dBW/m^2 for your uplink carrier

Occupied bandwidth is 1.4 MHz. Noise bandwidth ofcarrier assumed to be 1/1.2 of this.
So vabdwidth for C/N calvulation = 1.4 MHz /1.2 =  1166666 Hz.

Assuming transponders are 36 MHz wide, with EIRP=51.5 dBW saturated single carrier.
Assuming multicarrier output back off = -2 dB.
EIRP per 1.5 MHz (multicarrier operation) = 51.5 - 2 - 10log(1.5/36) = 35.7 dBW

The transponder 'gain' factor of 143.5 has been adjusted to give +35.7 dBW downlink EIRP for input PFD=-107.8 dBW.

The input figures are adjustable.  You need to overwrite the figures with your own more accurate information and assumptions.

Amend any white boxes and then click the calculate button to obtain results in the green boxes.

Any problems or comments please e-mail Eric Johnston   

Copyright (c) 6 July 2016 Satellite Signals Ltd All Rights Reserved
Last Revision: 12 April 2020