In case you still are thinking mobile networks will have a very hard time supplying bandwidth equivalent to fixed networks, consider the vision for fifth generation networks. The vision clearly requires releasing much more bandwidth for mobile use, especially in the gigahertz bands between 3 GHz and 300 GHz.
In the past, use of such frequencies for mass market communications has proven impossible. But Moore’s Law makes a difference. With cheaper, more powerful signal processing, communications service providers will be able to use spectrum previously unthinkable.
Any single device and user might have access to as much as 10 Gbps, from a small cell. In part, that is a result of physics. Gigahertz frequencies can support much greater delivered bandwidth per megahertz of raw capacity.
The simple reason is that coding efficiency ultimately depends on wavelength oscillations or frequency. The higher the frequency, the higher the information carrying capacity.
That, simply, is the difference between theoretical capacity of megahertz frequencies and gigahertz frequencies.
It’s the difference between millions and billions. A waveform at 800 MHz oscillates 800 million times a second. A waveform at 60 GHz oscillates at 60 billion times a second. Each oscillation supports, at a simple one bit per Hertz, a potential capacity related to the frequency.
The simple math is that, all other things being equal, gigahertz frequencies can carry 1,000 times more information than a megahertz frequency.
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