Re: Path Loss over distance...

Hi,

You're correct that the gain would increase the distance. It occurred
to me last night after I wrote my comment what your problem really is.
Your transmit power, 20 dB, is an error. If you transmit 20 dB (100
Watts) at 2.45 GHz, the local regulating bodies will probably shut you
down. It should be read 20 dBm instead, which is 20 dB with respect to
1 mW, or 100 mW. This would be 30 dB below what you were calculating
for your link margin. I think this will account for your correct
distance.

You're correct that the fade margin is included in the Friis
Transmission formula, but usually this has to do with loss due to
vegetation, rain, buildings, and the height of your antenna--which
affects how far it can transmit over the horizon. Only the last one
would apply to you, because you said you wanted to calculate in an open
field. There are several books out there that help you calculate this
margin, but mine (_Radiowave Propagation for PCS_) is at work right
now.

I hope my previous comment about dBm will help you.

Jeff Hazen, Wireless Engineer

.

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