NetStumbler.org Forums

Go Back   NetStumbler.org Forums > Newbie Lounge
Reload this Page How to compute signal level bars from SNR
Register Search Today's Posts Mark Forums Read

Reply
 
LinkBack Thread Tools Display Modes
Old 06-19-2005   #1 (permalink)
linhartr
Registered Member
 
Join Date: Jun 2005
Posts: 2
Question How to compute signal level bars from SNR
I'm writing a Perl script to read the ns1 files I collect during a site survey. 1st question is, right now I'm using the files from File-Export-Text but would prefer to read the ns1 files directly. Is the file format documented somewhere?

Second question, I want to figure out what the signal display bars would say (Excellent/Very Good/Fair/Poor) based on an arbitrary SNR value. I found the following web page but based on the values I'm seeing, I don't think it could be right.

http://www.osuweb.net/wireless/faqs.html

I did notice the web page is for 802.11b and not sure if it is different for 802.11g. Does anyone have a reliable source for this information? Thanks!
linhartr is offline   Reply With Quote
Old 06-19-2005   #2 (permalink)
Dutch
Humourless EuroMod.
 
Dutch's Avatar
 
Join Date: Mar 2004
Location: City of Mermaids, Denmark
Posts: 6,813
Quote:
Originally Posted by linhartr
I'm writing a Perl script to read the ns1 files I collect during a site survey. 1st question is, right now I'm using the files from File-Export-Text but would prefer to read the ns1 files directly. Is the file format documented somewhere?
www.stumbler.net - the NetStumbler/MiniStumbler prorgammer's own site.

Dutch
__________________
All your answers are belong to Google. SEARCH DAMMIT!
Warning. Warning.
Low C8H10N4O2 level detected. Operator halted....
Dutch is offline   Reply With Quote
Old 06-19-2005   #3 (permalink)
Thorn
Did you do the math?
 
Thorn's Avatar
 
Join Date: Apr 2002
Location: Villa Straylight
Posts: 10,098
Quote:
Originally Posted by linhartr
Second question, I want to figure out what the signal display bars would say (Excellent/Very Good/Fair/Poor) based on an arbitrary SNR value. I found the following web page but based on the values I'm seeing, I don't think it could be right.

http://www.osuweb.net/wireless/faqs.html

I did notice the web page is for 802.11b and not sure if it is different for 802.11g. Does anyone have a reliable source for this information? Thanks!
Their table is OK. What kind of values are you seeing, and why don't you think they are correct?

802.11g isn't any different.
__________________
Thorn
"I'm The Doctor. I'm a Time Lord. I am from the planet Gallifrey in the constellation Kasterborous. I'm 903 years old and I am the man who is going to save your lives and all 6 billion people on the planet below... You got a problem with that?"
Thorn is offline   Reply With Quote
Old 06-19-2005   #4 (permalink)
linhartr
Registered Member
 
Join Date: Jun 2005
Posts: 2
Thumbs up
Quote:
Originally Posted by Thorn
Their table is OK. What kind of values are you seeing, and why don't you think they are correct?

802.11g isn't any different.
I'm seeing values a lot higher than 26dBm. High 40's and low 50's.

BTW, thanks for the speedy reply!
linhartr is offline   Reply With Quote
Old 06-20-2005   #5 (permalink)
Thorn
Did you do the math?
 
Thorn's Avatar
 
Join Date: Apr 2002
Location: Villa Straylight
Posts: 10,098
Quote:
Originally Posted by linhartr
I'm seeing values a lot higher than 26dBm. High 40's and low 50's.

BTW, thanks for the speedy reply!
That would imply that you're either closer than is required for clear communications, you are using a high-powered AP/RF amplifier or both. How far away is the AP you are using to test?

It is also assuming that you are using a card which repports the Signal, Noise and SNR correctly (i.e. a Hermes chipset.) Any other card/chipset is suspect at best, and highly inaccurate at worst.

You're welcome.
__________________
Thorn
"I'm The Doctor. I'm a Time Lord. I am from the planet Gallifrey in the constellation Kasterborous. I'm 903 years old and I am the man who is going to save your lives and all 6 billion people on the planet below... You got a problem with that?"
Thorn is offline   Reply With Quote
Reply

« Ministumbler | Need help with a reflector design for internal antenna... »

Thread Tools
Display Modes
Linear Mode Linear Mode

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



Google
 
Web NetStumbler.org

All times are GMT -7. The time now is 02:21 AM.

Contact Us - NetStumbler.org - NetStumbler.com - Online Backup - Archive - Top

Powered by vBulletin® Version 3.6.8
Copyright ©2000 - 2008, Jelsoft Enterprises Ltd.
Content Relevant URLs by vBSEO 3.0.0 ©2007, Crawlability, Inc.


All messages express the views of the author and are for entertainment purposes only. Netstumbler.org cannot be held responsible for the authenticity of the content or the actions of its members. By using this site and its services, you warrant that you will not post any messages that are discriminating, obscene, hateful, threatening, or otherwise violates any laws and you release Netstumbler.org from any future claims of any kind whatsoever including, but not limited to, addiction and loss of productivity. All forum messages, private messages and any other content are properties of Netstumbler.org. Even if publicly available, personal or copyrighted information are not to be posted without the consent of the owner. Distribution of licensed and copyrighted materials in any way not endorsed by the copyright owner is strictly prohibited. You may not use this site and its resources to spam other sites or individuals or perform any action that violates any law. Items sold or bought in the For Sale forum are sold as is and no warranty or insurance of any kind is provided. Netstumbler.org cannot be held responsible for the outcome of any transactions and no warranty of any kind is provided, either express or implied. Vulgar words are not allowed in the subject lines ; they may be used in the message body in any forum. The Administrator, Super Moderators and Moderators of Netstumbler.org have the right to remove, edit, move or close any thread for any reason and to reveal your identity and other known information in the event of a complaint or legal action arising from any message posted by you.