Wireless router - Signal quality problems

[green granite]

Or just buy one of these: Compact High Gain Directional Corner Antenna for Wireless Networks : Wireless Network Antenna : Maplin

[Saab Dastard]

Yes - but check that the existing antenna is removable before purchasing!

SD

[Pontius Navigator]

Originally Posted by Saab Dastard

In theory, a metal shield at the PC antenna on the opposite side to the direction of the desired base station could be beneficial in helping to reduce the strength of unwanted signals - but only from that direction. It wouldn't help with signals from the same direction as the desired base station.

The real problem, though, is that the reflection of the signals coming from the desired base station (and any other extraneous signals) by the metal shield could cause destructive interference at the PC antenna and actually lower the strength of the desired signal!

Basically this is aerial theory. A TV array aerial has a line of 'directors' in front of the actual aerial and a large reflector behind the aerial. The aerial itself is a dipole sized to the central freqency band of the transmitted frequencies. The directors are set at wave-length distance to boost the signal and the reflector behind is similarly spaced to reflect the signal back. As SD says, if that interval is exactly wrong then the reflected signal will be 180 deg out of phase and cancel the signal.

For your router 'transmitter' you can have a reflector buy it must be at the correct distance otherwise it will cancel the signal. A program such as netstumbler will allow you to observe the signal/noise ratio as you move the reflector or as you angle the antenna.

[mad_jock]

The best shield for this situation would actually be dense but non-reflective material. Masonry and timber would be better than glass or metal.

As a note if you have a wacking great fish tank it will give issues as well if its between the laptop and router

[Saab Dastard]

Yup, sure will - those guppies sure do absorb radio signals! And as for the electric eels...

SD

[mad_jock]

Water

Well known method to use for shielding places you don't want people sniffing EM from.

Also used for shielding all things nuclear that are hot hot hot.

Can't claim the kill on that problem it was the big Russian speaking bloke who debugs in hex that did it. But we were all in the restaurant that was having the problem with its electronic POS waiter units. The 6'x8'x1' fish tank certainly screwed the signal.

[Saab Dastard]

Interestingly, while water is very, very good at absorbing RF, glass is quite good as a reflector / scatterer in its own right - and even better if it has a metal content or coating.

SD