Re: Solutions for long range (3-5KM) RF communication?

On Sun, 24 Apr 2005 00:16:31 +0000, Michael Noone wrote:

> Hi - I need to establish a bi-directional data link between a ground
> station and an aerial vehicle. Distance should be at most 3KM and should be
> in a relatively flat area, but there is the possibility that there will be
> buildings in the way, so the stronger the signal the better. As far as data
> rate goes, 10KBps would be great, but a lesser data rate would be OK as
> well. The ground station will have plenty of power available to it, but the
> aerial vehicle will have a much more limited power supply, so the less
> power it uses the better. Another limiting factor is weight and size -
> really the smaller the better when it comes to weight/size. Ideally I'd
> like to come up with something the size of an altoids tin.
>
> I have been looking at the Nordic Semiconductor nRF905
> (http://www.nordicsemi.no/index.cfm?obj=product&act=display&pro=83) - I
> have been told that it has a good range, but I have never heard numbers,
> and I don't know how to translate specs to numbers (ie how to go from mw or
> db to meters). Could anybody explain that to me? Or if it is fairly
> complicated - point me to a good resource on the topic? Obviously - I am no
> expert when it comes to RF. I have also looked at some RF chips made by
> Linx Technologies, though the Nordic chips are much more attractive
> (besides the awful QFN 32L package)
>
> So - does anybody have any suggestions as to good RF solutions for this
> application? Thanks so much for your time!

Chineese spider-skimmer WiFi? ;-)

http://www.usbwifi.orcon.net.nz/

--
Keith
.

Relevant Pages

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