T41 internal WLAN antenna, location & possible enhanceme

[tmattis]

Where exactly is the internal WLAN antenna placed in the T41 -
is it sitting in the left side of the screen, or over a bigger screen area?

Are there any known simple ways of increasing its range by adding an external metal thingy?

(I'm thinking of something similar to cut-open beer cans that is bent to form a "deep dish" parabolic for use with router antennas etc. So far I've only tried to hold large metallic cutlery near the screen, guesstimating the antenna placement, but never saw any obvious difference in directivity/sensitivity. If the exact antenna position is known, it should perhaps work to win a handful of dB's or two. My neighbor's glitching WLAN network is driving me crazy...;)

Thanks!

[richk]

The antenna is 2 wires (main and Aux) that go around the outside od LCD panel, inside the frame.

[tmattis]

The antenna is 2 wires (main and Aux) that go around the outside od LCD panel, inside the frame.

Does this imply a front/back directivity,
or are they like the standing antennas of an ordinary router?

[dr. zoidberg]

for a parabolic type reflector, you would have to place the source at the focus of the reflector. I don't see how this can be reasonably accomplished when the antenna is inside the LCD bezel. In any case, the gain would be highly directional.

If you have a router that can be customized (e.g. Linksys wrt54g) you could just crank up the transmission power of the router

[zverg]

Where exactly is the internal WLAN antenna placed in the T41 -
is it sitting in the left side of the screen, or over a bigger screen area?

Are there any known simple ways of increasing its range by adding an external metal thingy?

(I'm thinking of something similar to cut-open beer cans that is bent to form a "deep dish" parabolic for use with router antennas etc. So far I've only tried to hold large metallic cutlery near the screen, guesstimating the antenna placement, but never saw any obvious difference in directivity/sensitivity. If the exact antenna position is known, it should perhaps work to win a handful of dB's or two. My neighbor's glitching WLAN network is driving me crazy...

Thanks!

You can see the antenna locations on the screen. One is on the top (it's the plastic piece with the diagonal ridges), the other is on the right side (with similar ridges). The bluetooth antenna is on the left side near the bottom where there is a smooth piece of plastic.

[Johan]

I think you might find some useful information in --> this thread (see my second post of Jan 26, 2007).

If your neightbours WLAN is driving you crazy (and perhaps also vice versa?), this could be caused by both of you using the same ferquency. I guess that you have a wireless router or access point, so try check which channel it is set up using. It has a default setting, so if everybody uses that channel, some interference may occur (resulting in lower data rate).

To check what frequencies "are in the air" in your vicinity, try download the free - and very useful! - spectrum analyzer program --> NetStumbler.

Update: I recall to having seen - somewhere on the net! - a very simple and very cheap parabolic reflector, made of aluminum-coated paper; it uses the (typically) vertical mounted/polarized dipole antenna in a WLAN router/access point as the feed. Some shop (in England?) sell this thing; it comes in an envelope, you simply unfold it and mount it down over the dipole. It works! I just can't find it right now, but this patent is describing the principle. Super cheap!

You might play with a similar reflector behind your ThinkPad, but I don't think it is going to look exactly elegant...

If you really want to boost your range, disable the internal WLAN interface, get a PCMCIA WLAN interface with an external (e.g. 8 dBi colinear) dipole antenna - that will work!

Regards,

Johan

[dr. zoidberg]

Update: I recall to having seen - somewhere on the net! - a very simple and very cheap parabolic reflector, made of aluminum-coated paper; it uses the (typically) vertical mounted/polarized dipole antenna in a WLAN router/access point as the feed. Some shop (in England?) sell this thing; it comes in an envelope, you simply unfold it and mount it down over the dipole. It works! I just can't find it right now, but this patent is describing the principle. Super cheap!

I built my own from a template I found on the net which I then put on my router antenna. It wasn't worth it. There was a slight gain when I was in the direction of the dish but in any other direction, the signal to noise ratio was made worse (in certain places, significantly worse)

If you really want to boost your range, disable the internal WLAN interface, get a PCMCIA WLAN interface with an external (e.g. 8 dBi colinear) dipole antenna - that will work!

This is probably the best solution unless, like you said, there is interference being caused by something on the same frequency

[GomJabbar]

Here are a couple of articles I had bookmarked which you might find useful. Admittedly, they are a bit dated.

Minimizing 802.11 Interference Issues

Extending WLAN Range with Repeaters