Wireless LAN range

Hi

I've recently purchased a D-Link DWL-700AP and two DWL-122 USB wireless
adaptors for creating a 802.11b wireless network setup. I have deployed
the access point in the middle of the house and have tested the range of
the signal from a laptop.

Unfortunately the device does not extend any further than a few meters in
any direction. On one side of the house, it makes about 10m to the
end of the house and fails to cover the areas furthest away upstairs. On
the other side, there is a fairly thick wall in the way, and signal drops
off at about 5m. I have tested both USB adaptors in ad-hoc mode to see if
the AP may be faulty, but performance does not improve at all. Given that
this signal is not adequate for the task at hand, I will need to purchase
an aerial to improve the range.

I am naturally hesitant to risk buying any more equipment for fearing of
throwing good money after bad. I estimate I need to generate three times
the range horizontally, and cover the remainder of the upper level. I am
using the standard 2.5db gain antenna provided with the access point
currently. The following points are relevant.

* I don't think a directional antenna is the best way to go (as far as
I'm aware), I need to extend the range in both directions horizontal, and
up vertically. Unless I put a directional antenna at one end of my house
and direct it across the entire house (which seems to defeat the point of
the technique), it doesn't seem feasible. However I don't know much about
these things.

* I'm aware that you should have an antenna at both ends for best results,
but there's no way of doing this with the USB without opening it up. I'd
prefer not to do that.

* My calculations suggest that the DWL-50AT won't have the gain I require
to make the system work. I'm not sure what other aerials would be best for
this setup.

I wonder if anybody could give me some advice on this.

Thanks

B@za

On Thu, 27 May 2004 21:32:19 +0100, "B@za" <(E-Mail Removed)>
wrote:

>I wonder if anybody could give me some advice on this.

antenna gain is all about directionality, so higher gain antennae will
have a flatter radiation pattern (omni) or conical (directional).

Have you tried different channels in case its affected by interference
- channel 1 should go further as its lower frequency.

Is the AP up in the air, so that half its signal isn't disappearing
into the earth. VCan you stand it on a metal sheet eg a filing cabinet
or similar ground plane.

Have you tried different heights and orientations for the USB NICs to
find the best signal.

Phil

Hi

Thank you for your response

On Thu, 27 May 2004 23:44:23 +0100, Phil Thompson wrote:

>
> antenna gain is all about directionality, so higher gain antennae will
> have a flatter radiation pattern (omni) or conical (directional).

I would of thought omni would be better in my situation as I need signal
all around (although not equally in all directions). But I'm not an expert
on this.

>
> Have you tried different channels in case its affected by interference
> - channel 1 should go further as its lower frequency.

Yes, I've tried 1, 6 and 11. There seems to be no difference in strength.
Additionally I've been told that interference results in a high bad
packets count, something I seem not to be suffering. It seems
to me that interference is not a likely cause, although I can't be sure.

>
> Is the AP up in the air, so that half its signal isn't disappearing
> into the earth. VCan you stand it on a metal sheet eg a filing cabinet
> or similar ground plane.

The AP stands around 75cm off the ground. It stands on a wooden cabinet,
so moving it to metal may help, but would that be enough to
boost the signal substantially?

>
> Have you tried different heights and orientations for the USB NICs to
> find the best signal.

Yes, it seems little helps to resolve this problem. I found there are hot
spots around in which the access point can be reached at a very low
signal level as far as 15m's out, but nothing concrete. Mostly it's a
blackout with anything over ten meters.

Thanks

B@za

I have a Dlink 514 and also use the 122's.

My situation is: Router downstairs on a bookcase near the ceiling.
The 122's are upstairs at opposite end of the house ( approx. 25 feet
). The 122's actually hang off a world map on the wall. Using a
paperclip I can slide them back and forth until I get max signal.

The signal must pass thru 3 walls and the ceiling. I use a aluminum
parabolic reflector behind the antenna to focus the signal upstairs.
The adds about an additional 10 units of signal strenght. I always get
between 60-70 percent as measured on the 122 program.

I have WEP enabled using channel 10. Also, I bought an antenna from
Ebay that was advertised as bing 5 dbi and there was no improvement at
all.

What signal level are you getting ?? What material are your walls
made of ? My house has standard wood framing and drywall.

Kip



On Fri, 28 May 2004 00:26:17 +0100, "B@za" <(E-Mail Removed)>
wrote:

>
>Hi
>
>Thank you for your response
>
>On Thu, 27 May 2004 23:44:23 +0100, Phil Thompson wrote:
>
>>
>> antenna gain is all about directionality, so higher gain antennae will
>> have a flatter radiation pattern (omni) or conical (directional).
>
>I would of thought omni would be better in my situation as I need signal
>all around (although not equally in all directions). But I'm not an expert
>on this.
>
>>
>> Have you tried different channels in case its affected by interference
>> - channel 1 should go further as its lower frequency.
>
>Yes, I've tried 1, 6 and 11. There seems to be no difference in strength.
>Additionally I've been told that interference results in a high bad
>packets count, something I seem not to be suffering. It seems
>to me that interference is not a likely cause, although I can't be sure.
>
>>
>> Is the AP up in the air, so that half its signal isn't disappearing
>> into the earth. VCan you stand it on a metal sheet eg a filing cabinet
>> or similar ground plane.
>
>The AP stands around 75cm off the ground. It stands on a wooden cabinet,
>so moving it to metal may help, but would that be enough to
>boost the signal substantially?
>
>>
>> Have you tried different heights and orientations for the USB NICs to
>> find the best signal.
>
>Yes, it seems little helps to resolve this problem. I found there are hot
>spots around in which the access point can be reached at a very low
>signal level as far as 15m's out, but nothing concrete. Mostly it's a
>blackout with anything over ten meters.
>
>Thanks
>
>B@za

On Tue, 01 Jun 2004 15:37:09 -0400, evans wrote:

> I have a Dlink 514 and also use the 122's.
>
> My situation is: Router downstairs on a bookcase near the ceiling. The
> 122's are upstairs at opposite end of the house ( approx. 25 feet ).
> The 122's actually hang off a world map on the wall. Using a paperclip I
> can slide them back and forth until I get max signal.
>
> The signal must pass thru 3 walls and the ceiling. I use a aluminum
> parabolic reflector behind the antenna to focus the signal upstairs. The
> adds about an additional 10 units of signal strenght. I always get
> between 60-70 percent as measured on the 122 program.
>
> I have WEP enabled using channel 10. Also, I bought an antenna from
> Ebay that was advertised as bing 5 dbi and there was no improvement at
> all.
>
> What signal level are you getting ?? What material are your walls made
> of ? My house has standard wood framing and drywall.
>
> Kip
>
>
The D-Link software doesn't work on Windows XP with me, and I tend to use
Linux anyway, so my signal strength will vary to yours. Walls in my house
are a bit of a mix. It's an old house and has been extended as time goes
on. It's generally a mix of stone, brick and drywall. In one direction,
the path is clear enough, no walls and signal is good. Upstairs signal is
generally good, apart from at the outer edges of the house. I suspect the
reason for this is that the signal needs to travel through a stone wall
instead of plaster board.

The signal in another direction is very bad, there are two walls in this
direction, one stone and one brick. This is a pretty bad situation, I'd
agree which is why I need significant wireless signal boosting. There is
no obvious place to reposition the access point to avoid this issue.

In terms of signal strength, the signal is suffering upstairs towards the
outer parts of the house. Down towards the worst area, the signal barely
passes through the first wall before failing.

I could buy two access points, and configure one as a repeater using an
directional antenna to link them up wirelessly. But that sounds like a
very expensive option although it should work. I tested all WAP channels,
but found there was no obvious difference between them. I have WEP enabled
too, but it seems not to matter. Disabling it had no effect either.

I have heard others say the 5dbI antenna from D-Link makes no difference.
I was thinking about buying the 7.8dbI onmi-directional antenna, but it
may not make any difference.

B@za

B@za <(E-Mail Removed)> wrote:
> The D-Link software doesn't work on Windows XP with me, and I tend to use
> Linux anyway, so my signal strength will vary to yours. Walls in my house

The D-Link 122 was working fine on my Win2000 laptop. I gave it to my
son-in-law who could see NetStumbler signal, but never connect with WinXP.
Then he decided he wanted wanted Linux, and loaded Linux on the laptop,
wiping out the WinXP. He hasn't been able to get the 122 working under
Linux. What did you do?

---
Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8-122.5