Uneven router signal

I am using Network Stumbler to monitor the signal levels of my Netgear router.
While it is understandable that the level drops every time I position myself between the
router and my laptop ( average signal value is -58dBm, at a distance of approx. 30
feet ), I cannot explain why, all conditions being equal, sometimes the level drops down
by a good 10 o 15 dBm, with sudden dips and then recovers after 10 seconds or so. Again,
the surrounding environment is the same, no microwave ovens kicking in, only a cordless
phone which is always on, actually. Looks like the router is misbehaving.
Any clues ??
Thanks,

Mike

Mike

On 19-Apr-2007, "Mike" <> wrote:

> I am using Network Stumbler to monitor the signal levels of my Netgear router.
> While it is understandable that the level drops every time I position myself
> between the
> router and my laptop ( average signal value is -58dBm, at a distance of approx. 30
> feet ), I cannot explain why, all conditions being equal, sometimes the level drops
> down
> by a good 10 o 15 dBm, with sudden dips and then recovers after 10 seconds or so.
> Again,
> the surrounding environment is the same, no microwave ovens kicking in, only a
> cordless
> phone which is always on, actually. Looks like the router is misbehaving.
> Any clues ??
> Thanks,

You don't say what antenna at the PC end. Often with built in antennas
the PC case can screen the antenna, which is also being subject
to nearby networks, even if they are on a different channel.
If these are strong the compete with the desired signal and affect
the automatic gain control.
I've found adding a simple foil reflector to my USB wireless adapter,
and locating it for maximum pickup, helps to reduce fluctuations
of level.
By raising gain in one direction you reduce the level of signals
from rear and side of the direct path, whilst increasing the
desired signal. Which is of course the purpose of reflectors.
As a result there can be an improvement of signal quality,
and a rise in link rate.
USB wireless adapters on the end of a lead can be
positioned for best pickup, and most USB adapter utilities
show signal strength and quality. Signal quality seems
the most important measure, and signal quality falls
with multipath propagation.

ato_zee@hotmail.com

Hi
It is a normal Wireless behavior.
As to do with the surrounding and stabilization circuits of the Wireless
transmission.
2.GHz is the same frequency as the Microwave and has the same qualities,
i.e. it gets absorbed by water molecules.
Jack (MVP-Networking).

"Mike" <> wrote in message
news:...
>I am using Network Stumbler to monitor the signal levels of my Netgear
>router.
> While it is understandable that the level drops every time I position
> myself between the router and my laptop ( average signal value is -58dBm,
> at a distance of approx. 30 feet ), I cannot explain why, all conditions
> being equal, sometimes the level drops down by a good 10 o 15 dBm, with
> sudden dips and then recovers after 10 seconds or so. Again, the
> surrounding environment is the same, no microwave ovens kicking in, only a
> cordless phone which is always on, actually. Looks like the router is
> misbehaving.
> Any clues ??
> Thanks,
>
> Mike
>

Jack \(MVP-Networking\).

"Jack (MVP-Networking)." <> wrote in message
news:%...
> Hi
> It is a normal Wireless behavior.
> As to do with the surrounding and stabilization circuits of the Wireless
> transmission.
> 2.GHz is the same frequency as the Microwave and has the same qualities,
> i.e. it gets absorbed by water molecules.
> Jack (MVP-Networking).
I see. That is why my wireless network is so sensitive to humidity.
Jim

Jim

My laptop has a built-in wireless adapter (Intel PRO 3945ABG), so no external antenna is
present. There are no nearby networks, at least they are not reported by Network
Stumbler.
Shall I buy a USB dongle ? If so, will I have to disable the wireless card ? Is it
convenient ?
Thanks,

Mike
-------------------------------------------------------------------
<> wrote in message news:...
>
> On 19-Apr-2007, "Mike" <> wrote:
>
>> I am using Network Stumbler to monitor the signal levels of my Netgear router.
>> While it is understandable that the level drops every time I position myself
>> between the
>> router and my laptop ( average signal value is -58dBm, at a distance of approx. 30
>> feet ), I cannot explain why, all conditions being equal, sometimes the level drops
>> down
>> by a good 10 o 15 dBm, with sudden dips and then recovers after 10 seconds or so.
>> Again,
>> the surrounding environment is the same, no microwave ovens kicking in, only a
>> cordless
>> phone which is always on, actually. Looks like the router is misbehaving.
>> Any clues ??
>> Thanks,
>
> You don't say what antenna at the PC end. Often with built in antennas
> the PC case can screen the antenna, which is also being subject
> to nearby networks, even if they are on a different channel.
> If these are strong the compete with the desired signal and affect
> the automatic gain control.
> I've found adding a simple foil reflector to my USB wireless adapter,
> and locating it for maximum pickup, helps to reduce fluctuations
> of level.
> By raising gain in one direction you reduce the level of signals
> from rear and side of the direct path, whilst increasing the
> desired signal. Which is of course the purpose of reflectors.
> As a result there can be an improvement of signal quality,
> and a rise in link rate.
> USB wireless adapters on the end of a lead can be
> positioned for best pickup, and most USB adapter utilities
> show signal strength and quality. Signal quality seems
> the most important measure, and signal quality falls
> with multipath propagation.

Mike

On 20-Apr-2007, "Mike" <> wrote:

> My laptop has a built-in wireless adapter (Intel PRO 3945ABG), so no external
> antenna is
> present. There are no nearby networks, at least they are not reported by Network
> Stumbler.
> Shall I buy a USB dongle ? If so, will I have to disable the wireless card ? Is it
> convenient ?
> Thanks,

If it's working stick with what you have got. If it was a PCI card with
integrated antenna, then it might have been worth pulling the card
and trying USB.
Problem with fiddling is that your connection may stop working,
and you then get into advanced trouble shooting, like is it
WZC, DHCP, or just an IP address problem? Such as the new
adapters drivers can't find the router to lease an IP address,
hence no DNS connection, and it all goes tits up.
There are also some shiddy USB wireless dongles around,
I prefer the ZyDas based ones, but they are hard to find,
and I never got on with D-Link USB wireless adapters.
So before looking for USB wireless dongles do a bit
of research, most of the better reviews are in the American
magazines, who don't seem to be in the pockets of the
mfrs (advertising revenue) and say it as it is, warts
and all. But a bit og Googleing should find some info.

ato_zee@hotmail.com