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Radio link budget calculator - for line-of-sight radio or microwave link.

Complete all white boxes and then click the calculate button to obtain results in the green boxes.

If you are not using dish antennas at one or both ends, then estimate the gain in dBi of the yagi, dipole, tin can, horn etc that you have. e.g dipole gain = 3 dBi, tin can 7 dBi, bi-quad 8 dBi, helix 12 dBi, jagi 10 dBi etc. Input numbers into the white box for antenna diameter and keep altering the number till the antenna gain is as you want it.

Frequency GHz
Transmit antenna diameter m
Transmit antenna aperture efficiency e.g. 0.65
Transmit antenna transmit gain dBi
Transmit antenna, power at the feed W
Transmit EIRP dBW
Range km
Path (spreading) loss dB
Power flux density at receive end dBW/m^2
Bandwidth Hz
Receive antenna diameter m
Receive antenna aperture efficiency e.g. 0.65
Receive system noise temperature (antenna+LNA) K
Signal power at output of receive antenna dBm
Receiver sensitivity (see manufacturer spec e.g -80 dBm)
Receive margin dB (0-5dB=marginal, 10-15dB=good)
Receive antenna gain dBi
Receive G/T dB/K
Link C/N dB

I would be interested for anyone to evaluate this calculator and put right any errors, make suggestions for improvements etc.

General purpose satellite link budget calculator

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