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Original wording of question: What is fractional network access?
I'm having trouble figuring out what this term actually means, though I can find a ton of whitepapers about how some-standard-or-another means to support it.
I know it's related to the fact that wimax makes use of it's operating on subchannels, but 3g takes up an entire band. How would that work with 3g, then?
Another way of looking at it would be to say that conventional signalling methods have a small number of discrete channels which will never interfere with each other, while CDMA has a large number of virtual channels that will occasionally, randomly, collide. Conventional signalling methods will have low error rates but have a hard capacity limits. CDMA does not have a hard capacity limit, but as the number of logical channels in use increases, so will error rates. CDMA can't achieve as high bandwidth as other technologies, but unlike other technologies it allows point-to-point communication without arbitration.
Why CDMA is able to use whole band, when Wimax is subchanneled?
Because code division is based on decorrelation (orthogonality) of signals as opposed to traditional separation across frequency spectrum and/or time. So CDMA allows to operate concurrently, the same time, in the same frequency band, in the same geographical spot.
To understand how it works, look at M-Sequencies.
From high level look at spectrum, code division, walsh patterns etc. as different types of orthogonality. They all are equally limited in terms of informational capacity with presence of noises. But frequency spectrum is simplier technically, because it is a scalar, not some "code space" thing.
