|MetaGeek Wi-Spy 2.4 GHz Spectrum Analyzer|
|Summary||Suprisingly good, most inexpensive 2.4 GHz spectrum analyzer you can buy.|
- Consists of USB dongle and Win XP / 2000 application
- Linux / MacOS software also available
|Pros||• Real RF Spectrum analysis for $99|
• Good detection range
• Recording and playback
|Cons||• Misleading amplitude information|
• Fixed amplitude range
• Coarse frequency resolution
When I first heard about a 2.4GHz spectrum analyzer for $99 bucks, I figured someone must have slipped a decimal point. But it turns out that MetaGeek's Wi-Spy is real, does work, and can really be yours for a Benjamin, with change back to boot!
What it is
Wi-SPY consists of a small USB module that's about the size and form factor of a small USB flash drive and a small software application. Figure 1 shows that the module is a JUNO-USB dongle, manufactured by Unigen, an OEM / ODM of memory, DC-DC power converter, wired and wireless communication, and flash products.
Figure 1: Unigen USB receiver
The Wi-Spy module is a Cypress WirelessUSB design, using a Cypress CYWUSB6934 LS 2.4GHz DSSS Radio SOC and CY7C63743 enCoRe USB Combination Low-speed USB & PS/2 Peripheral Controller. The key relevant tidbits that I picked up during a quick read of these datasheets is that the radio has a receive sensitivity of -90 dBm and has a top data transfer rate of 62.5 kbits/sec.
The software that comes with Wi-Spy runs on Win XP and 2000 only and requires the installation of Microsoft .Net Framework 1.1 or higher. The dongle is USB 1.1, so will also work with USB 2.0. If you're not a Windows fan, you'll be happy to know that Mike Kershaw, author of Kismet, has developed an open source version of the Wi-Spy software that runs on Linux, BSD, and Mac OS X. The blurb on MetaGeek's website says "This application is under heavy development and is quickly progressing to become feature-equivalent to the Windows Wi-Spy software." I worked only with the Windows version, but you can find out more about Mike's version here.