[MLB-WIRELESS] Antenna Overlap

[Drew]

Thing to remember about RF, is that despite every manufacturer 
publishing range specs, "range" means nearly nothing. It's an 
approximation based on a lot of assumptions, which are usually wrong. 
The range of a node is based on its own input power, cable loss, gain, 
AND the power, loss, and gain of the receiving side. So this means your 
omni can have different ranges depending on the equipment at the other 
side. A better figure for estimating connectivity are system operating 
margin (SOM) calculations. Locfinder does these for you if both sides 
fill out their interface info completely. As for high gain dish, 
focusing the signal into a small area lets them send signal farther in 
that area, and also lets them receive signal from farther away in that 
area.
 
Drew

> One of the things im not really clear on with respect to Antennas and 
> the whole RF thing;
>  
> If i have a low gain omni with an effective range of say... 1km and i 
> have a high gain dish (enough to include the omni in the signal range) 
> some 15km away pointed at the omni, i understand that the omni can 
> pick up the radiated signal from the dish, but is the dish able to 
> pick up signal from the omni at that range? and if so why is that? :)
>  
> Feel free to post an RTFM link if this has been asked and answered. Im 
> new to the whole RF side of things.
>  
> Thanks,
>  
>
> *________________________**
> *jason* brice**
> */senior network engineer
> /kiandra system solutions
> level 9, 455 bourke st melbourne vic 3000
> (t) +61 3 9600 1639
> (f) +61 3 9600 1656
>
>  
>
>  





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