I don’t think that you can do something like that with the 802.11. As QpoX explained the LOS is the biggest problem. You can achieve something with different omnis but for more than 500m you will need a very good coverage of the terrain, especially if it is full of buildings..
Our network coverage is extensive in an area which is “communicationally challenged” (very little comms at all) - and after a lot of “client pressure” we ventured into VoIP and now have ± 100 numbers up and running from the client’s premises off our own SIP server on Asterisk.
Because our HQ is based in a small community we have had lots of enqiries about VoIP mobile phone “lines” - ie: open some of the 2.4GHz BSS to allow for authenticated phone MACs to make calls… which led to some “experimentation”.
Be it as it may - we found that the new generation of GSM cell phones (Nokia E65 etc) have 100mw 2.4 GHz capability - and that lots of cell phone carriers were VERY interested n this…
We continue - with good success I might add… it works well and the cell phones register with the SIP server nicely and when “out of range” de-register.. so it actually makes things easy. Initially it impacted our call desk but seems to have settled in nicely now.
Please, phone with 100mW at 2.4 GHz capability at which distance from AP works?
What dbi gain must have access point for working at maximum distance that allowing TX of phone (Nokia E51, E65) ?
Maybe this: http://www.solwise.co.uk/voip-phones-si680h.htm
The AccessPoint needs to be in LOS! and forget to use a Nokia phone! they only send out a few mW (as what i know of)…
But try to buy a AP and a Phone and do a test setup then change settings, antenna’s and so on to improve your setup.
If you are lucky…
But it still depens on iron in the houses and so on…
I’ve had one where the AP was 2meters from a computer in another room and in the wall there was Aluminium foil (to keep heat in the rooms) there was no signal at all…
But if you are in LOS from the phone to the AP, a 100meters should be no problem…
The way to go around is really WDS and setup more AP’s where there are holes…
We run a VoIP system for our customers (CPE's with VoIP phones) ...
We decided to try and energise all our "hotspots" in our town...
(these are essentially 5 GHz incoming with 2.4 GHz Omnis for the client's PC's Laptops etc) -
to allow users to "buy" a line for cell phones which had wireless installed. These users would then be authenticated on the "hotspots" and make calls as and when they were close to any of the Omnis....
Typically we see anything between 30 metres in and around buildings and up 120 metres in free air.
Either way the users who have subscribed to the service are happy - as an experiment it has worked well.
Of course - you will always get those who want to "push the boundries" - so if this is not enough - or the phone will not make it - ??? - we'll have to wait for phones with R52H's built-in....
We have also installed Indoor AP's with 7 dBi Whip antennas for customers and these deliver 30 metres easily.