This is an interesting wireless network design scenario.
One acre is roughly 208.71 feet × 208.71 feet square.
So 4.5 acres would be roughly 522 feet x 522 feet, assuming that the property is square.
WIFI 6 (802.11 ax) has a maximum range of roughly 175 feet.
This estimate works great for the signal coming from the AP,
but WIFI is a 2 way street and you don't specify what the clients are.
Let's assume there is a clear line of site from the AP to the clients
with no obstructions. Let's also assume that all of the clients are
WIFI 6 capable and have a maximum range of 100 feet.
Based on this, I estimate you would need a minimum of 15 APs,
with 9 APs along the sides of the square and 6 more deployed
around the interior of the square. You would probably want
to use patch antennas around the sides of the square and omni-directional
antennas inside the square. Mounting each of the APs and antennas on a 10 to 12 foot
pole would probably be sufficient.
If the clients are only capable of WIFI 5 or even 4, then you would need to
double or triple the number of APs.
This is a rough calculation and a real site survey would be much more accurate.
The Meraki mesh design guide has some excellent recommendations on which APs
need to be wired repeaters or wireless gateways.
https://documentation.meraki.com/MR/Deployment_Guides/Mesh_Deployment_Guide
Based on the recommendations from the guide, all of the APs on the outside
of the square need to be wired and at least one of the APs in the middle of the square
would need to be wired too. And since the network deployment is outside,
I would recommend that you run fiber for all of the wired connections.
You would also have to run power to all of the APs too.
Since you would have to run power to the AP locations, you might as well run fiber too.
You would also need some power surge protection and proper grounding too.
Something like these adapters would work well for the AP side of the fiber connection:
https://www.perle.com/products/media-converters/poe-media-converters.shtml
Multi-mode fiber would be sufficient, no need for single mode fiber and the additional expense.
You would probably need a Meraki MS410-16 switch to connect all of the APs together.
Their are more factors to consider such as what the internet connection is and what
the requirements are for client bandwidth and what the clients are actually accessing over
the wireless network.
In order to take full advantage of the MR86 higher bandwidth, you would have to go with
10 gigabit over fiber, along with an MS425-16 switch and at least an MX105 firewall
to handle a 3 gigabit internet connection. I don't know if anyone even makes a 10 gigabit
fiber to multi-gigabit PoE converter. If their were a lot of clients consuming a lot
of bandwidth, an MX250 or MX450 would be a better choice.
The MR76 AP would probably be more than sufficient and much cheaper.
This would still be a significant capital expenditure to purchase and deploy.
That's my 0.02 worth 😉
