I am working on reasons why we should use a system such as canopy instead of blasting 802.11g over our coverage area.
I know that Canopy is much better than 802.11b, but I understand that 802.11g and Canopy use the same modulation technique. Can someone point me to a site or some technical explanations as to why Canopy or some other vendor’s last mile solution is better?
Thanks
Kevin
Modulation: 802.11a/g uses OFDM for better speed; Canopy uses High Index BFSK for better noise rejection.
Speed: 802.11a/g links peak at 54Mbps (when using OFDM), and double that on some proprietary implementations; Canopy peaks at only 10Mbps to the SMs. (These are “link” speeds; throughput is about 70%, and that’s shared between users.)
Noise: 802.11a/b/g all need a Signal-to-Noise-Ratio of, I believe, 10dB; the Canopy needs only 3dB.
Your choice depends on a lot of factors, but if you’re an ISP and need some range and reliability, there’s no comparison: you’ll be better off with Canopy. I use 802.11a&b on some links – primarily to minimize cost – but I much prefer the Canopy system.
One of the most impressive features of Canopy is its ability to reuse channels. All the APs are synchronized so that multiple APs can coexist on the same frequency. There are design rules that need to be followed, but they’re straightforward.
The downside to this ability is the cost can quickly become prohibitive in low-density installations. The upside is in high-density installations: you still need only 3 non-interfering channels, even with dozens of AP clusters.
Enjoy your research!