[WISPA] formulas behind pathloss+RSSI calculators?

[Chuck McCown - 3]

Here is an example.
TX power of 30 dBm (1 watt)
+ 10 dB antenna gain = 40 dBm EIRP
- Path loss (say 10 miles at 915 MHz)  116 dB
+ 10 dB RX antenna gain
= -66 dBm RX signal level
----- Original Message ----- 
From: "Chuck McCown - 3" <chuck at beehive.net>
To: <scubacuda at gmail.com>; "WISPA General List" <wireless at wispa.org>
Sent: Wednesday, July 16, 2008 5:31 PM
Subject: Re: [WISPA] formulas behind pathloss+RSSI calculators?


> Tx power + antenna gain - free space path loss + rx antenna gain =rssi.
>
> ----- Original Message ----- 
> From: "Rogelio" <scubacuda at gmail.com>
> To: "WISPA General List" <wireless at wispa.org>
> Sent: Wednesday, July 16, 2008 5:24 PM
> Subject: [WISPA] formulas behind pathloss+RSSI calculators?
>
>
>> I'm looking for the math behind this website
>>
>> http://www.distributed-wireless.com/calculators/pathloss_RSSI.html
>>
>> I know the free space loss calculation (20 * Log10 (frequency in MHz) +
>> 20 * Log10 (Distance in Miles) + 36.6), but what is the connection
>> between that and the RSSI at that distant point?
>>
>>
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