Range for two WRT54GL bridged

Hello:

I am thinking of setting up two Linksys WRT54GL routers, in a bridged configuration so that they talk wirelessly to each other directly. My question is, what is the estimated range if these two routers are connected wirelessly, with their default antennas that they come with? In our case, we will have a direct line of sight between them, but the distance is about 800 feet. I am trying to figure out if the default antennas might be enough or if we'll need to purchase new antennas.

Thank you very much for all feedback,

-- Chris

Reply to
chris
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Get a pair of directional antennas. Make sure they're firmly mounted as to stay aimed at each other. You don't need the second antenna on the WRT54 series, at least not for a point-to-point link like this. Antennas are cheap and you'll get better data rates.

Reply to
Bill Kearney

Just out of curiosity, how are you getting power there? I had an outbuilding that was about 1000FT from the house, but had an underground power cable to it from the house. I used powerline networking as the bridge (one router output to the others wan input, same ssid, created a huge covered area)

Reply to
Peter Pan

| I am thinking of setting up two Linksys WRT54GL routers, in a bridged | configuration so that they talk wirelessly to each other directly. My | question is, what is the estimated range if these two routers are | connected wirelessly, with their default antennas that they come with? | In our case, we will have a direct line of sight between them, but the | distance is about 800 feet. I am trying to figure out if the default | antennas might be enough or if we'll need to purchase new antennas.

At 800 feet I'd say it's next to impossible on the provided antennae, and probably difficult on anything but the highest gain external antenna (e.g. might work but be quite slow). For this kind of distance I'd go for a 1 meter minimum parabolic dish on each end. Look for one that has at least 24dbi gain.

Are there any objects in between? Walls? Trees? People?

Will you be using the default firmware, or an alternate firmware?

My understanding is the WRT54GL by default is an access point and I learned the hard way an access point is not supposed to talk to another access point. I don't know if the included software can be told to do otherwise (either AP to AP or BR to BR, or just AP to BR) or if you need to get some better software. I'm curious what you manage to get working (at a shorter distance when testing, not at 800 feet as I think that will fail with the default antennas) and how. I'd like to do the same thing (at 20 feet) with the firmware it comes with so I can start using it before building custom firmware images.

I also am curious how a 2-antenna device would be connected to external antennas. Since I don't know what the WRT54GL is actually doing with each RF port (especially on transmit ... both at the same time, or just the one that seemed to be more reliable for the intended peer device).

Reply to
phil-news-nospam

|> In our case, we will have a direct line of sight between them, but the |> distance is about 800 feet. I am trying to figure out if the default |> antennas might be enough or if we'll need to purchase new antennas. | | Get a pair of directional antennas. Make sure they're firmly mounted as to | stay aimed at each other. You don't need the second antenna on the WRT54 | series, at least not for a point-to-point link like this. Antennas are | cheap and you'll get better data rates.

Which antenna is the 1st and which antenna is the 2nd?

What to do with the one not connected to the directional antenna?

  1. Terminate it?
  2. Leave it open?
  3. Leave the original ducky on it?
Reply to
phil-news-nospam

snipped-for-privacy@groupinfo.com hath wroth:

Well, let's do the math. See:

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the procedure.

The rubber ducky antennas have about 2dBi gain on a good day. Since there's no feed line, the coax cable losses are zero. I'll assume line of sight and no Fresnel Zone infringement, which is a rather dubious assumption. Since everyone seems to crank up the power on the WRT54G/GS/GL boxes, I'll assume 100mwatts of tx power. This is going to be a stretch so I'll use the 2nd slowest 802.11g wireless connection speed of 12Mbits/sec OFDM, which should give 6Mbits/sec thruput.

TX power = +20 dBm TX coax loss = 0 dB TX ant gain = 2 dBi Distance = unknown RX ant gain = 2 dBi RX coax loss = 0 dB RX sens = -84 dBm (at 12 Mbits/sec) Fade margin = 20 dB

Plugging into:

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various guesses for the distance until I get 20 dB of fade margin (SOM). I get a range of about 0.15 miles or: 0.15 miles * 5280 ft/mile = 800 ft.

2.4Ghz 0.8 Fresnel Zone at midpoint of an 800ft span is a radius of about 7.2ft.
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's a nice way of saying that your antennas have to be at least 8 ft off the ground or you will have additional losses. Also, no junk within a radius of 7.2ft of the line of sight at midpoint.

It should work if everything is perfect. The numbers only get worse, never better. You gotta have good line of sight, no junk in the Fresnel Zone, no interference from other users, and lots of luck. Personally, methinks it's going to be a stretch at 800ft with the stock rubber ducky antennas. I would attach a pair of directional gain antennas instead of trying to do it with the stock antennas.

Reply to
Jeff Liebermann

Thank you very much for the info. I will post the results if & when we get this up.

Best,

-- Chris

Jeff Liebermann wrote:

Reply to
chris

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