Long wireless point-to-point connection with 802.11n


I'm new in this jkind of technology, so I question if despite 802.11n being still in the third draft, it is possible to create directional long point-to-point connections with 802.11n... I wanted to do a backbone with higher throughput than possible with 802.11g for 2 miles (3km) connections.

Since 802.11n uses MIMO smart antenna technologies and consequently two or more antennas to transmit using the multipath for transmission enhancement, the fact of using multiple directional antennas pointing to the same destiny will work?? Do you know any recommended equipment?

I thank your answer in advance ;)

Rodrigo Selada

------------------------------------------------------------------------ View this thread:

formatting link

Reply to
Loading thread data ...

At almost two miles, the antenna spacing on consumer devices for diversity isn't going to be effective. You'd be better off running commercial grade equipment on 2.4 or 5.8 Gig. You can do it for under $700 of electronics.

As always, the LOS and 60% Fresnel clearance rules apply.

Reply to

Godigo hath wroth:


No, you cannot do a long range link with Pre-802.11n Draft 2. No, you cannot do 2 miles at speeds faster than 802.11g (i.e. faster than 54Mbit/sec).

The long range Pre-802.11n Draft 2 link will be impossible for the simple reason that you'll need 3 external antennas at each end. Also, external antennas suitable for MIMO are not commonly available. Most Pre-802.11n Draft 2 routers do NOT have removable antennas.

The long range on faster than 54Mbits/sec is a simple matter of fade margin. At 54Mbits/sec, you'll need an impossibly strong signal to get such speeds at 2miles. It can be done, but you won't like the price or size of the antennas. I can grind the numbers (later) if you want to see them.

Close. The Airgo spatial mux mutation of Pre-802.11n Draft 2 spatial multiplexing requires that the various streams to have slightly different path lengths to work. If they're all the same, the interleaved carriers will "collide", and you won't get very much thruput. It's possible to derrange the multiple antennas to insure different path lengths, but that becomes ugly with larger arrays.


Some light reading, which might explain a few things:

(A bit old, from 2003, but still useful).

Reply to
Jeff Liebermann

Cabling-Design.com Forums website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.