As noted in my previous blog, spectrum analyzers give you a whole new dimension in monitoring, troubleshooting, and optimizing wireless networks. This all sounds great, but what’s the rub?
Traditional RF spectrum analyzers are bulky, pricy, and for the most part, designed for engineers to operate and interpret the displays. Some models offer storage, but not the long term and frequent snapshots required for post mortem analysis of intermittent problems or “something bad that happened at 2 a.m. in the warehouse.”
Some smaller hand-held and even PDA-based RF Spectrum analyzers help with the portability issue, but are often limited as to what they can do and how quickly they can sweep and sample the spectrum and do all the FFT math in real time. Think of it like VoIP – the better the sampling rate (G.711 vs. G.723 for instance), the better the quality.
Cognio, a WildPackets partner, has built a patented Spectrum-Analayzer-On-A-Chip or SAgE for short. SAgE can perform some 150,000 spectrum measurements per second and is available as an RF sensor or notebook PC Card. The sensors are designed for distributed RF analysis and location triangulation whereas the notebook card is for suitable for portable use.
Interpreting the information is still an issue so Cognio has developed software to perform signal analysis and categorize the interferring device. Events are logged and alerts can be generated. At one time, I was told that the Cognio engineers got a little carried away and even started identifying brands of cordless phones. That’s a bit much for me but there are some other really cool things you can do with the product. Check it out.