This month marks the five year anniversary of Wi-Spy and Chanalyzer. A few days ago I was looking back at screenshots of Chanalyzer 1.0 (a.k.a. Wi-Spy Viewer) and laughed at…

This month marks the five year anniversary of Wi-Spy and Chanalyzer. A few days ago I was looking back at screenshots of Chanalyzer 1.0 (a.k.a. Wi-Spy Viewer) and laughed at how basic it was. The data resolution was so bad the screenshots look like they are from an Atari console game 🙂 But even that very first version of our software contained some significant innovations in PC-based spectrum analysis that have since been adopted industry-wide.

Here’s a quick tour of the evolution of MetaGeek products, showing the progression from Wi-Spy Viewer 1.0 to Chanalyzer Pro, and how they have led the whole industry forward over the past five years.

December 2005

Before I invented the Wi-Spy, Cognio’s Spectrum Expert was the only PC-based spectrum analyzer on the market. It was PCMCIA based and covered the 2.4, 4.9 and 5 GHz bands. The software was fairly advanced with automatic device classification, device finder, waterfall view and a few bar graphs showing channel usage. The user interface was overly complex though and with a price tag of almost $4,000 it was clearly aimed at enterprise customers only.

When I released Wi-Spy it was clearly not in the same league as the Cognio Spectrum Expert, but for $99 WLAN administrators finally had visibility at the RF layer and could troubleshoot physical layer issues in their wireless networks. The first Wi-Spy model was a retrofitted wireless mouse dongle (notice the “connect” button underneath the “I”).

The radio receiver only had a 5-bit RSSI, which severely limited the amplitude range and the frequency resolution was fixed at 1 MHz steps. The software only had current, average, and max traces. But Wi-Spy was the first USB spectrum analyzer, making it accessible to modern laptops and desktops. The Wi-Spy Viewer 1.0 software was the first to label the frequency axis by either MHz or Wi-Fi channel and to fill in the area underneath the max and average traces instead of just drawing a line (the solid areas are easy to visualize at a glance).

Nuts About Nets – 2007
Ubiquiti – 2009
Airmagnet – 2009


Development in 2006 was slowed by my “day job,” daily runs to the post office to ship orders, and tech support. So the only new feature that was released in 2006 was the addition of a waterfall view. The software could toggle between the standard spectrum analyzer view and the waterfall view, but couldn’t show both views at the same time.


2007 was a big year for the industry. We released Chanalyzer 2 along with Wi-Spy 2.4x, and Cisco announced the acquisition of Cognio (which was finalized in early 2008).

Chanalyzer 2.0, released in February 2007, was a complete redesign of the Wi-Spy Viewer application. This was the debut of the density view in PC-based spectrum analyzers. Chanalyzer 2.0 also introduced stacked views aligned by frequency for easy visual comparison. This layout has become the defacto standard and should look familiar to anyone who has used a modern PC-based spectrum analyzer.

Nuts About Nets – 2007
Ubiquiti – 2009
Airmagnet – 2009

In May 2007 Chanalyzer 2.1 added the ability to pause and rewind live data similar to using Tivo to replay and skip TV. We also unified the timeframes of each view so that if the waterfall view was showing 30 seconds, the density and planar views were also showing 30 seconds of data.

In June 2007 we released Wi-Spy 2.4x; the first Wi-Spy designed specifically as a spectrum analyzer. The difference in data resolution can be readily seen by comparing the Chanalyzer 2.0 screenshot to that of Chanalyzer 2.1 above.


We started off 2008 with the first release of inSSIDer, an open source replacement for the aging and abandoned NetStumbler tool. inSSIDer 1.0’s primary innovation was its network strength over time graph.

Chanalyzer 3.0 was released in March 2008. Its innovative features included: Signature overlays for common 2.4 GHz transmitters, Data Inspector (displaying detailed information about the data point the mouse hovered over), user-created notes embedded in recording, and arbitrary length timeframe instead of set timeframes of 1 min, 2 min, 5 min, etc.

Chanalyzer 3.1, released in July 2008, merged the Wi-Fi network information gathered by inSSIDer with the spectrum analysis gathered by Wi-Spy. The table of Wi-Fi networks from inSSIDer was condensed and placed in the Chanalyzer sidebar.

Now that we had data from the Wi-Fi radio as well as the Wi-Spy we decided to visually merge the data by adding network overlays to the density view. Now users could visually see the frequency and amplitude of Wi-Fi networks along with non Wi-Fi signals.

Airmagnet – 2009

Chanalyzer 3.1 also introduced the ability to stream data from a remote Wi-Spy via a TCP connection.

Airmagnet – 2010

Although our software and hardware had improved significantly since 2005, Wi-Spy remained a 2.4 GHz only product until the release of Wi-Spy DBx in January 2009. Wi-Spy DBx was the first USB spectrum analyzer to cover all Wi-Fi channels, which was a requirement for many enterprise customers. Prior to the release of Wi-Spy DBx if you need spectrum analysis of 5 GHz Wi-Fi, you had to use Cognio Spectrum Expert with a PCMCIA card.

Airmagnet – 2010

Chanalyzer 3.2 was released to add Wi-Spy DBx support to Chanalyzer. It also added the ability for users to control the hardware settings for start and stop frequencies, frequency step size and resolution bandwidth. This allowed users to view a single Wi-Fi channel at high resolution or to quickly scan an entire band. Users could also now gather data from multiple Wi-Spy simultaneously.

From 2005 to 2009 the only real competition to Wi-Spy was the Cognio Spectrum Expert, which remained largely the same from the initial release of Wi-Spy until the acquisition of Cognio by Cisco effectively stopped development altogether. This left Cognio’s largest OEM, Airmagnet, without a spectrum analyzer. In April 2009 Airmagnet released the first successor to the Cognio OEM’d Airmagnet Spectrum Analyzer. Even though Cognio was considered the only real “enterprise” Wi-Fi spectrum analyzer, Airmagnet modeled the Airmedic interface and views on Chanalyzer, adopting many of our innovations and visual improvements.

In June 2008 we released Chanalyzer Lite, which shipped with our new Wi-Spy 2,4i, a replacement for the original Wi-Spy. Although Chanalyzer Lite was designed as a low-end product, we added a few new features along with some of the tried and true features from the rest of the Chanalyzer family. We added a 3-D view to incorporate frequency, amplitude and time into a single graph. We also made the data inspector follow the mouse instead of being relegated to the sidebar.


In February of this year Airmagnet introduced their very first USB spectrum analyzer, the Spectrum XT, claiming it was “the industry’s first USB-based professional spectrum analyzer solution.” Spectrum XT only supported 32-bit versions of Windows.

With another USB-based professional Wi-Fi spectrum analyzer finally on the market, we upped the standard by introducing Chanalyzer Pro in June. Chanalyzer Pro was built on a completely new architecture, allowing more flexibility to store supplemental data like Wi-Fi information, as well as greater flexibility to mix and match the data displayed in the graphical views.

The biggest visual change was the modification of the now standardized stacked views with a playback waterfall view along the left, which displays an aggregated waterfall view of the entire recording. By using the time-based data in the navigation controls, users can now jump directly to trouble spots in a recording instead of playing it back from start to finish. It also makes it easy to quickly compare the real-time data to previous data without jumping back and forth.

Inspired by Edward Tufte, we added spark lines to all data tables to provide a brief historical snapshot of signal strength. The density view coloration was also tweaked to use the same amplitude color scale as the waterfall view, unifying the color scale across all views. The density is now shown via the transparency of each pixel. The unified color scale makes it easy to match up signals in the density and waterfall views. All frequency/amplitude data was merged into the density view, rather than having two separate views with the same axis.

Device Finder and Click-and-Drag to zoom take advantage of the configurability of the Wi-Spy hardware. To make it easier for users to report back to their customers and bosses, we also added a block-based report builder.

One of the most requested features over the past five years was device classification, and it’s something we’ve experimented with over the years, struggling to find a reliable classification method that didn’t produce substantial false positives. This year we decided to get serious about device classification. Along with improved algorithms internally, Chanalyzer Pro displays a confidence level for the classification match and also displays a signature overlay, giving users the power to determine for themselves if the classification given by Chanalyzer Pro is likely correct or not. The device classification in other spectrum analyzers is a black box with no visibility into how or why a signal was classified, nor how confident the software is that its classification is correct.

In order to build a bigger and better classification signature library, in October we added the ability to create custom classifier signatures with the option to submit the signature to our signature library. We also gave users the ability to adjust the minimum confidence threshold required for automatic classification.


Airmagnet – December 2010

2011 and Beyond

Ever since we introduced the first Wi-Spy five years ago MetaGeek has led the industry with breakthrough innovations that have improved PC-based spectrum analysis, and we have some great things planned for the coming year including firmware updates to improve data collection, classification enhancements, and more detailed Wi-Fi information. Our team is passionate about RF troubleshooting and data visualization; for us it’s not about sales and revenue, it’s about making products that truly kick ass.

Ryan Woodings
Chief Geek