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Aire - WinXP WiFi discovery software

PostPosted: Thu Jun 03, 2004 1:11 pm
by GovCon
Cordially announce: AIRE is an 802.11 network discovery utility for Microsoft Windows XP (it works great on my main pc but not on the laptop for some reason with a Linksys WUSB11 v2.6)
It reads out the SSID channel and signal strength in a crap but useful computer generated voice.
Its got a signal level display as well as a few bugs like announcing that i was using channel 2000 and something :rolleyes: (comes in Spanish too)

http://www.astalavista.com/index.php?section=dir&cmd=file&id=1706
http://www.robota.net/article?id=1024

Please feel free to post your results and compatability reports.

PostPosted: Mon Aug 09, 2004 5:50 pm
by GovCon
Having recently gotten 2 new cards I have experimented with this a bit more.
It works with my Sitecom Wireless Network card 11M (WL-011v2) and my Intel Pro/Wireless 2011B LAN PC card (WPC2011BWW)
You can open more than one instance of the program at a time and therefore use 2 different cards at the same time.
Ive figured out the bug when it’s reading out the network channel too, its reading out the frequency, 245700. Another slight disadvantage of using this program is that it does not automatically store the networks it’s found in a log file.
It’s quite Netstumbler-esque so if you’re having problems getting your card to work with Netstumbler this is a definite alternative.

PostPosted: Mon Aug 09, 2004 10:30 pm
by bigpappasmurf
This is pretty cool, but it crashes when it detects more than one network, by the way, i've only tryed it with my linksys 802.11 B/G card. I'll try it with the Avaya Orninoco clone later or tomorow.

PostPosted: Thu Aug 12, 2004 11:58 pm
by Serviceman
Could anybody explain me how exactly relates RSSI with SNR and Signal+ as indicated in NetStumbler?

PostPosted: Fri Aug 13, 2004 4:17 am
by Thorn
Serviceman wrote:Could anybody explain me how exactly relates RSSI with SNR and Signal+ as indicated in NetStumbler?


RSSI: Received Signal Strength Indication (AKA "Signal")
SNR: Signal to Noise Ratio
Signal+: Highest recorded Signal on a particular AP

Don't confuse 'Signal', 'Noise' and 'SNR' with 'Signal+', 'Noise-' and 'SNR+'.

The columns without the signs are the current reading, with those marked with the signs (+ , -) are the maximum recorded for each AP .

PostPosted: Fri Aug 13, 2004 5:06 am
by Serviceman
I understand what the terms mean, but I don't know the equation between RSSI and say SNR, if there is any.

PostPosted: Fri Aug 13, 2004 5:17 am
by Thorn
SNR is the difference between the Signal level and the Noise level.

Signal - Noise = SNR

Example:
Signal = -70dBm
Noise = -100dBm

-70 - -100 = 30

Therefore: SNR = 30dBm

Read through the Antenna FAQs, there is a fair amount of RF information in there.

PostPosted: Sun Aug 15, 2004 11:07 pm
by Serviceman
Thorn wrote:SNR is the difference between the Signal level and the Noise level.


I know this terms pretty well, but what I don't know, how it mathematically relate with RSSI, if at all.

PostPosted: Mon Aug 16, 2004 4:27 am
by wrzwaldo
Serviceman wrote:I know this terms pretty well, but what I don't know, how it mathematically relate with RSSI, if at all.


Here you go.

[quote]
Because the RSSI detector is a nonlinear detector, it changes the Signal to Noise Ratio (SNR) of the signal that goes into it. The key to the ASK sensitivity calculation is the SNRout vs SNRin curve of the RSSI detector.

Once we know the SNRout vs SNRin relationship, the steps to finding the ASK sensitivity for a given Noise Figure, IF Bandwidth, and Data Rate are given below.


1. Determine the Eb/No needed for a target BER (10-3 in this example) then calculate the SNR from the Eb/No by using

SNR = (Eb/No) * (R/BBW)

Where R is the data rate and BBW is the Data Filter bandwidth.
2. Reduce the SNR calculated from the previous step by the ratio in dB of the IF (pre-detection) BW to the Data Filter BW. For instance, a 600 kHz IF BW and 6 kHz Data Filter BW means a 20 dB reduction in the SNR. This is the SNR of the signal coming out of the RSSI detector before the Data Filter gets rid of the high frequency noise (assumed to occupy the IF BW). At sensitivity, this ratio is usually negative in dB.
3. Use the RSSI SNRout vs SNRin curve to find the SNR at the input to the RF or IF Amplifier and RSSI detector. You actually use the curve "backwards" to find SNRin given the SNRout you calculated in Step 2.
4. Use the SNR formula for the front end of a receiver to find the signal level at the receiver input. This is the sensitivity, S.

S = (SNRin) * (kTBIFFS)
Where kT is the noise spectral density at 290 K (-174 dBm/Hz) BIF is the IF (pre-detection) BW, and FS is the system (not just the front-end) noise figure of the receiver.

Because the RSSI detector is a logarithmic detector, the SNR input-output relationship can be expressed in a closed-form expression, albeit a messy one. An old paper published in the IEEE Transactions on Aerospace and Electronic Systems[1] derived the expression and plotted the SNRout vs SNRin curve. The curve in the article is small and doesn

PostPosted: Tue Aug 17, 2004 2:03 am
by Serviceman
Thanks!

Spyware ?

PostPosted: Sat Aug 21, 2004 12:14 pm
by yoshiguy
anyone know if this program might have spy ware in it ?

PostPosted: Sat Aug 21, 2004 3:01 pm
by GovCon
Highly Unlikely. I’ve been using it for months and haven’t seen a sight of anything spyware like, a fully updated Ad-aware scan reveals nothing and even if it was spyware in any form it would be crap as its not starting itself on boot, and i look everywhere.

Any reason you are asking?

PostPosted: Sun Aug 22, 2004 12:00 pm
by yoshiguy
I ask because it's not an open source product and I just want to sure. I had problems before with spyware.

How is the program? Can you do packet capture ?

PostPosted: Sun Aug 22, 2004 7:02 pm
by GovCon
1) Netstumbler is not open source how do you know its not spyware?
2) The world has had problems with spyware before, get ad-aware or spybot search and destroy and use your common sense!
It does not do packet capture, it is very similar to netstumbler in features.

PostPosted: Tue Aug 24, 2004 7:19 pm
by yoshiguy
You have a point but netstumbler is such a popular program. If there was, someone would have notice by now.
Aire is still new.