As part of the second annual Boise Bot Competition, the Idaho-based Discovery Center also hosted a Tech Fest which offers local companies an opportunity to talk about problems they are solving with technology and more importantly – how it works. Being the geeks we are, we jumped at the opportunity to participate. Saturday morning Chris, one of our software hackers, and I headed off to join in the fun.

The MetaGeek demonstration table was right inside the entrance to the Discovery Center. We had Chanalyzer running on a variety of different devices, including a MacBook Pro, Windows virtual machine,
a Windows 8 tablet PC, an Android tablet, and an iPad. We were monitoring and displaying the 2.4GHz, 5GHz, 868MHz, 900MHz, and 950MHz spectrums using Wi-Spy 2.4x, DBx, 900x and 950x. We were also monitoring the 2.4GHz spectrum at my house remotely using a prototype of our remote Wi-Spy.

Over the course of the day, about 450 people came down to the Bot Competition. Most of the attendees weren’t familiar with spectrum analysis and were very curious about what Chanalyzer was showing them. When we explained that Wi-Spy and Chanalyzer allowed them to see the invisible wireless communications and interference going on around them, they were amazed.

Most of the attendees weren’t familiar with how Wi-Fi works, so we did a good bit of educating. The 2.4GHz band at the Discovery Center was pretty crowded. There were 3 public and 1 private wireless access points, as well as 3 dedicated access points used to control the FIRST Robotics Bullbots, built by local high school students. As a result, we were able to give some compelling demonstrations of adjacent channel interference. By juxtaposing the displays for the empty 5GHz band and the congested 2.4GHz band, we were able to provide a great visual explanation for why the industry is moving toward 802.11a/n.

We also brought a fixed-frequency wireless video camera with us so that we could do more interactive interference demonstrations. This lead to one of the most exciting parts of the day for me. We were finishing up an interference demonstration and turned off the video camera. To our surprise, a strong fixed frequency signal continued to transmit, on the same frequency our camera had been using. After we verified that the camera was indeed completely powered off, we decided to track down the source of this new interferer.

We fired up Chanalyzer Pro on the Windows 8 tablet, and hooked up a Wi-Spy DBx with the Device Finder 2.4GHz directional antenna. We zoomed into the mystery signal, and then launched the Device finder in Chanalyzer Pro. I wandered around the Tech Fest, and the device finder indicated that the signal was coming from the entry foyer. As I walked that direction, I was expecting that maybe the signal was coming from the reception desk in the foyer. To my surprise, the signal continued to grow stronger as I passed the desk and approached the outside doors. As I exited the building, the source of the signal became pretty obvious. The Boise Police Department were demonstrating their Bomb Robot in the parking lot. Sure enough, as I approach the robot, the signal became very strong! Apparently, the bomb robot uses 2.4GHz for its video feed back to the operator.

I was pleased that Device Finder had worked so effectively to track down the source of the interference, but I was even more impressed with using Chanalyzer Pro on the Windows 8 tablet. The tablet form factor is great for using Device Finder, and the using a touchscreen to interact with Chanalyzer for zooming in to a frequency, starting the device finder feature and adjusting the timeframe was very natural. I’m very excited about the things we’ll be able to do with Chanalyzer and Wi-Spy on touch-based devices.

Chris and I had a great time geeking out at the Boise Bot Competition and talking to people about spectrum analysis and Wi-Fi. We thank the Boise Bot Competition for inviting us and the Discovery Center for hosting.