taken from http://www.willowvale.ndo.co.uk/umts.htm
This page is all about mobile phones, on which I have spent a considerable part of my working life. My first experience of this type of technology was back in 1987, when I worked for Ferranti Creditphone on their CT2 project called Zonephone. Later, I worked on CT2 for what was then Racal Orbitel. I then worked in the radio fire alarm industry for many years, and returned to mobile technology with Panasonic in 1999. Myself and a colleague worked at their mobile phone laboratory just before the British Government's auction for the third generation license.
It is tempting to go into great detail here on radio aspects of mobile phone technology, but I will refrain from doing that. Suffice to say that a radio engineer often has a different understanding of the possibilities and limitations of technology than the software engineer. Many of the details I want to get over are contained in the report below which can be downloaded if you so desire. It tries to present some basic information about current 2G GSM technology and CDMA technology as used on 3G mobile phones without getting bogged down in maths. However, it is surprising that in the rush to get into 3G the basics of radio engineering so carefully developed during 2G development appear to have been set aside. GSM is a very successful system, the result of nearly 20 years toil, and at best CDMA is a less successful system by comparison.
Predictions? 3G will reach a maximum speed of 28kbps; the only 4G that you might get will use broadcast technology for the downlink because basic radio engineering mandates that this is so. There will be no faster point-to-point networks because the simulations are done with a piece of wire replacing the radio interface.