MetaGeek Wi-Spy 2.4 GHz Spectrum Analyzer

Reviews: Networking

Author:
Editor:
Sponsor:
Published:

Richard Poelling
Kurtis
MetaGeek
Jun. 19, 2006

<< Previous

Next >>

Installation

Upon insertion of the CD, you will be presented with a menu. Basically, you can install the software, run it from the CD, or view the included movies which contain examples of various types of interference from items such as cordless phones and microwaves. These are great starting points and can be fun to watch too, although watching the microwave can be a bit disconcerting. It makes you wonder just how good that internal shielding REALLY is. Kind of gives you that warm feeling when you are nuking a burrito!

Installation of the software was very easy. The CD which shipped with the Wi-Spy was version 2006.3.17.0, for my general testing purposes I downloaded the latest version from their website, 2006.4.22.0. If you choose to use the CD, you can run the software directly off it without installing. This is assuming you have the .NET 2.0 framework installed on your system. This is a nice feature because you can easily plug the device in, drop the CD in the drive and get a good feel for your environment without having to install anything on your computer. You don't even have to go through any driver installation prompts. This is especially useful if you are using someone else's laptop or computer which would probably be the case if you were to help out a friend or co-worker.

Software Overview

Starting the Wi-Spy software presents you with a large graphical display, which is referred to as the Analyzer view. Along the bottom, you have either the frequency or Wi-Fi channel displayed. In the latest version of the software, they have added support for Zigbee , which is a standard for home automation and sensors which also uses the 2.4 GHz spectrum.. Along the top you have the following options regarding the recording of spectrum information: begin a new recording, open an existing recording, restart recording, play recording, pause recording, and fast forward a recording. For viewing and working with incoming data or playback of previously recorded sessions, you have the option of choosing either the Analyzer or Spectrographic view. Again, when working with the graph, you are able to toggle on or off the data trace, the average trace or the max trace to get the view which most suits your needs. Finally along the top you have two additional buttons which toggle on or off the marker and the high amplitude line. When the marker is activated, you can have it follow any of the three streams of data, either the average, max, or the incoming data stream. As you move the marker, it will report the actual frequency it is on in MHz at the top of the graph.

As the device picks up signals, they are presented on the graph as the data line (yellow). This line is always moving as the information is being recorded. The red portion of the graph represents the average signal. This is by far the most important aspect of the graph. As the signal stays high in a particular spot, you will see the red average begin to creep up. It is this high average which will present itself as interference on your devices. It is the average signal which begins to rise when a large amount of information is transferred, such as copying over multiple gigabyte files. The maximum signal on the other hand only tells you how strong the signal was at a given point in time. After a couple of minutes, you will begin to see a standard bell curve shape where a wireless signal exists. This does assume you are only looking at one channel. I set a single AP on channel 7 which gives me a very defined shape surrounding that channel. Highlighting that channel colors the graph in such a way as to show where the signals from that channel will fall. Again, this is assuming you are looking at a single AP. Obviously, having two AP's, even 1 channel apart will change your graph. Basically, if you don't see a lot of red peaks, then your interference shouldn't be too bad.

Besides the Analyzer view, the Wi-Spy has the ability to change to a spectrographic view. This view shows the signals in relation to time. The amount of time displayed can be changed in the preferences ranging from 2 minutes to 24 hours. This type of trace would be an excellent way to locate time dependant interference as well as how long the interference is lasting. A single 24 hour recording would obviously enable you to get a view of a whole day. If you set your trace right, you could probably see when people nuked their coffee or lunch! When you compare the two views, the spectrograph makes the microwave interference far easier to see.

Being able to see the information in front of you is nice, but an analytical tool is only as good as its output. The Wi-Spy records each session into a CSV file which is easily read by excel or most standard spreadsheet programs. Opening this file, you will find the frequency listing along the top and below that the actual signal reading. The traces are generated by the program as it reads the files as well as the average peak information. Any graphical view you have can easily be copied and pasted by way of standard Ctrl+C functionality. You also have the ability to save the image in one of several formats: PNG, JPG, BMP, GIF, and TIF.

<< Previous

Page 2 of 4

Next >>

Page 1: Introduction & First Looks
Page 2: Installation & Software Overview
Page 3: Testing & Quality Check
Page 4: Conclusion

Subscribe to Wireless [more info]

Add Comment

4 User Comments

1 - Posted by Kurtis on June 20, 2006 - 12:04 am

DIGG it:
http://digg.com/technology/If_you_suffer_from_chro...

2 - Posted by PennyManDeux on June 20, 2006 - 12:58 am

Diggity dugg!

3 - Posted by Kurtis on June 21, 2006 - 3:27 pm

Cool, we got Slashdotted yesterday, thanks to PennyManDeux!
http://hardware.slashdot.org/article.pl?sid=06/06/...

4 - Posted by Rich on June 21, 2006 - 3:38 pm

Yes, those were some interesting comments on their site......

Add Comment

To add a comment without being a member, you may omit the password field, but you must enter your name (or nickname) along with your comment. * Denotes required fields.