VHF communication - sensitivity check for receivers
Transmitted power from your receiver which may include LNA / PA / etc = -97 dBm = 127W Approx
SINAD is same as Signal to Noise Ratio - >10dB
Generally, the sensitivity of any device is the minimum i/p signal (power in W or dBm) required to drive your receiver keeping the SNR and input power on mind. There should be few formulas which i cannot recollect. Maybe you can check on google or anyone else could be of better help.
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No.
-97 dBm = 0.2pW
-97 dBm = 10dBμV @ 50 Ohm
Online calculator: http://www.giangrandi.ch/electronics...l/decibel.html
ya, its 0.2pW. i did a quick pen paper calc and dont know where i went wrong !
But thats very low power ..
From my knowledge in aircraft industry minimum SINAD requirement is 12dB (and not 10dB).
Anyway, here is a nice paper from Aeroflex that explain SINAD measurements:
http://www.aeroflex.com/ats/products.../530/sinad.pdf
You would like to measure the sensitivity of the radio ?
Connect a signal generator to input, adjust a FM modulation within specification say 1kHz of modulation frequency,5kHz FM deviation or more.(NBFM)
Check the SINAD at the audio output by decreasing RF output level of the generator and when you see SINAD=10-12dB, stop it and read the RF input level.
Consider cable losses and connecor losses and make them calibrated well.
Receivers DONT transmit power they receive .... thats where you went wrong ;)
the -97 dBm for SINAD not less than 10 dB. referred to by the OP is the receiver sensitivity to an incoming signal
Dave
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