What’s Going on with the 3.65 GHz Band?

I saw another good blurb in the Rural Spectrum Scanner this past week on the 3.65 GHz band. The big issue in this range is a required "contention protocol" that the FCC has mandated. This is an approach not to dissimilar to the approach used in WiFi or ethernet where radios first listen for traffic then talk. The problem is that it is not a very spectrally efficient way to handle radio polling. As you might expect the FCC did not specify what contention protocol companies should use resulting in some confusion. In any event, some comments by industry have asked the FCC to remove this requirement altogether, which is a bit problematic as it was designed to protect the Fixed Satellite Service stations grandfathered in the spectrum. Also, the spectrum is not exactly unlicensed (although the FCC probably intended to lean in this direction) technically. It requires the registration of base stations on a non-exclusive basis. Jeff Thompson at Towerstream likes to call this approach "lightly regulated". In an of itself that is no bad idea. Opinions on what to do with this spectrum are all over the shop. Some favor switching it all to licensed bands. Others say licensed in urban areas, non-exclusive in rural areas. Ultimately the FCC is going to have to re-work its Report and Order to re-define this spectrum a bit. Once accomplished though, it is potentially very valuable spectrum. It would also be very easy (and economical) to re-tune existing 3.5 GHz WiMax gear for this range. Tim Sanders tim@thefinalmile.net www.thefinalmile.net www.wimaxglobalnews.com

The contention protocol requirement for the proposed 3.65 GHz band is to allow equitable sharing of the band in a geographic area with a minimum of interference to the various users. It was deliberate on the part of the FCC not to mandate a contention protocol, but to let the industry “sort it out” as to what makes the most sense to the industry as a whole.
The contention protocol requirement is not intended to protect the satellite earth stations - that’s done by the FCC mandating geographic exclusion zones. If you wish to operate 3.65 within those exclusion zones, you need to obtain concurrence from the operator of the satellite earth station.
Said by Steve Stroh April 13, 2006 at about 12:58 pm