dold@05.usenet.us.com hath wroth:

>John Navas <spamfilter0@navasgroup.com> wrote:
>> On Sat, 24 Mar 2007 23:12:04 +0000 (UTC), dold@05.usenet.us.com wrote in
>> >the reflector is not only 13dB stronger, it's more stable.
>
>> More stable??? How and in what way?
>
>It may be that the signal with the reflector is at the upper limit of what
>Netstumbler will display, but the signal reading provided is steady.
>without the reflector, there are fluctuations in the signal level.

Close, methinks I have a better guess. I've also noticed that
directional antennas are more stable (less variations in signal pickup
versus time). My guess(tm) is that an omnidirectinal antenna picks up
far more reflections with longer delays than a unidirectional antenna
pointed directly at the signal source. Less reflections means less
reinforcements and less cancellations, which means it's more stable.

>> measurements. My preference is to use a radio with good real-time
>> signal monitoring capability.
>
>I don't bother installing manufacturer client software, if that's what you
>mean. I think perfmon is adequate, and it's already there on WinXP, not
>something that has to be added, learned, or preferred.

No opinion, but I have an alternative. At a given signal strength,
thruput and speed are inversely proportional. If I lock down one,
signal strength becomes proportional to the other. Instead of
measuring signal strength, which tends to be rather erratic, I like to
measure thruput. I lock the speed to 54Mbits/sec, ignore the signal
strength, and measure megabits/sec thruput using Iperf.
<http://dast.nlanr.net/Projects/Iperf/>

I don't really know if this is the superior method, but it does have 2
advantages:
1. It does the measurement with traffic. Measuring signal strength
without any traffic moving results in some bizarre numbers. For
example, I know one wireless client (name withheld due to internal
politics), that always resets its indicated speed to 54Mbits/sec when
traffic stops even momentarily.
2. It takes into consideration any interference and reflection
effects. Interference has no effect on signal strength. However, it
has a huge effect on data thruput.

On the down side, it's kinda hard to make pretty looking antenna
patterns using data rate instead of signal strength. Oh well.

Back to working on taxes. Don't post anything interesting or I'll
never get this [deleted expletive] done.

--
Jeff Liebermann jeffl@comix.santa-cruz.ca.us
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558