2 WLAN PCI Cards + Linux(?) = repeater/relay

Hi! I'm building a WiFi home network and I need to make a signal repeater (relay?) using PC with 2 PCI Prism 2.5 cards. Is it possible?

It should be a "transparent" device that will take the signal from the top of the roof and transport it into my apartment (and vice versa). The ultimate goal is to connect laptops to the AP which can't be seen from inside of my apartment (but I see it clearly from the roof) and the interval between roof and AP is almost 800m (so even if I could see the Access Point from my apartment, wifi devices from the laptops won't reach it). I don't want to make AP or anything like that. I want to simple connect my home devices to master AP at the lowest cost (I already have a old PC Box and 2 Prism Cards).

Reply to
Booski Cinek
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Lets see if we have this straight:

*you have a wireless hotspot or somesuch 800m from your building. *From the roof, you can connect to it. *From inside your apartment, you can't.

You want some device that will connect to the AP, then rebroadcast to your apartment.

The simplest would be to put a wireless bridge on the roof with a suitable antenna pointed at the hotspot, then drop ethernet cable down to your apartment. Unless someone objects, you can probably just drop it down the outside of the building. You might be able to chain the bridge onto a wireless router or AP on the roof, but that will broadcast to your entire apartment building, and probably some of the neighbouring ones.

Thats what you're doing tho !

AFAIK client PC cards don't have a non-client mode, and anyway can't act as infrastructure servers. You do need an AP for that. Mark McIntyre

Reply to
Mark McIntyre

not exactly

yes, but only using exterior antenna with higher gain than antennas in my laptops


No. I want device that will let my laptops connect _directly_ to the AP, so each of them would get their own IP and bandwith. In other words, I need a device that will help my laptops connect to the master Acces Point. Something that will make possible to use single antenna by 4 computers.

No, because in that case I would have to share single bandwith and single IP with 4 computers.

No, I'm not.

Yes, they have. You can use Linux + HostAP drivers + WLAN Card with Prism 2.5 chipset to build Access Point. There are plenty of tutorials on the net.

Reply to
Booski Cinek

Yes, this is called "hardwiring the PCs to the bridge on the roof" and is what I described... :-)

Seriously tho, you can't do that, the antenna is either connected to a bridge, or its connected to a single client, and then rebroadcasts either wirelessly or via wires.

If you have a single antenna you have to do that.

Sure, and the prism card in my actiontec router does that too, via suitable firmware / sw in the router. But then its no longer a client card. Mark McIntyre

Reply to
Mark McIntyre

Mark McIntyre wrote: >> No. I want device that will let my laptops connect _directly_ to the AP,

Ok, I get it. So, what I want to do, is a wireless-wireless bridge. I have 2 PCI WiFi cards, so one will be connect to antenna on the roof and second will be connected to another antenna in my apartment. I want send everything that 1st card get to 2nd card and vice versa. Is it possible? I read about wireless-ethernet bridge, but I couldn't find anything about wireless-wireless bridge.

Ok, but is it changing anything for me? It's still possible with HostAP and Prism 2.5 cards.

Reply to
Booski Cinek

That'd require an very long antenna lead, and you'd lose virtually all signal in the cable. Its not going to work, I strongly suspect.

Jeff Liebermann can probably do the maths for you if you supply all the relevant data eg cable run lengths and type, antenna type, gain and so forth, cable impedance, exact AP or card model and revision number, exact topology of your location and so forth.

sure, route from one card to the other. If using Windows, enable ICS between them. If using linux, just enable routing. By the way, what you're building is called a "router".....

Frankly it'd be a lot simpler (and more likely to work) to buy a pair of cheap APs which have bridge mode, hook em together with Cat5 and put one (in bridge mode) on the roof hooked to your directional antenna, and the other (in AP mode) in your apartment. Mucking about with a pair of old client cards and a junk PC is going to be painful and time consuming. Mark McIntyre

Reply to
Mark McIntyre

Don't be so sure. I will use 20m H1000 cable with 20dBi antenna. So it shouldn't be that bad.

Why router and not a bridge?

The problem is, that I just can't put on the roof anything else than antenna.

hooked to your directional

But what you described is very similar to my idea. The only difference is, I will use WLAN PCI Cards (which can work as AP with HostAP) instead of AP. And maybe they're old, but it's still a very good piece of hardware (Just google for them - they work perfect with proper firmware).

Reply to
Booski Cinek

If you decided to do this already, why did you ask ?

Do the maths for your antenna cable. At 2.4Ghz the attenuation in cable is quite high.

Reply to
Mark McIntyre

Because I'm totally newbie in WiFi and I wanted to make sure that it will work. Actually I'm still a little afraid that it won't work as I imagine. And you really helped me with all this answers you gave. I'm serious. Big thanks for you.

I know, but, as I said, I just don't have other options. So let me summarize:

  1. The cable between antenna on the roof and WLAN Card is quite long, but I don't have any choice, so I will use low attenuation cable (H1000) and some hope;)
  2. The scheme of my network is:

master AP : : : antenna on the roof | | 20m H1000 cable |

1st WiFi PCI card working as AP Client | | bridge (powered by Linux) | 2nd WiFi PCI card working as AP Server : : : 5 computers with WiFi cards

And from the master AP point of view it should look like that:

[ m a s t e r A P ] : : : : : : : : : : : : : : : : : : : : 1st 2nd ...... 5th comp. comp.

Am I right?

legend: | - wire : - wireless

Reply to
Booski Cinek

Sure you do. Run Ethernet cable to the roof; put a client wireless-Ethernet bridge on the roof; and power the access point with POE (power over Ethernet).

Reply to
John Navas

Booski Cinek hath wroth:

H1000 coax cable is about 1dB for every 5 meters. Your 20meter run will have 4db of loss plus about 1dB for the connectors for a total of

5dB. As a rule of thumb, 6dB loss is half your distance. 12dB is 1/4 the distance. You distance will be about half of what it might be if the radio was attached to the 20dBi antenna.

Please do the link calculations. See: |

formatting link
you have problems with some of the guesswork, there are many other examples in alt.internet.wireless where I have explained how it works.

Reply to
Jeff Liebermann

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