User's Manual

Product Brief – Airborne SDIO/SPI 802.11b/g Radio Quatech, Inc.
846-8310-240 June 2010 15
EIRP (dB) = TxP + TxA – TxC
Link Margin (dB) = EIRP – FPL + (RxS + RxA – RxC)
Where: TxP = Transmitter output power (dBm)
TxA = Transmitter antenna gain (dBi)
TxC = Transmitter to Antenna coax cable loss (dB)
FPL = Free Path Loss (dB)
RxS = Receiver receive sensitivity (dBm)
RxA = Receiver antenna gain (dBi)
RxC = Receiver to Antenna coax cable loss (dB)
This is a complex subject and requires more information that is presented here,
Quatech does recommend at least looking at the subject and evaluating any
system at a basic level.
It is then possible, with a combination of the above items and an understanding
of the application demands, to achieve a link quality optimized for the application
and host design. It is important to note that this is established with a combination
of hardware selection, design choices and configuration of the radio.