If fifth generation mobile networks supply 10 Gbps of bandwidth for every user or device, then even using all other available techniques–multiple input, multiple output radios, directional and phased array antennas, beamforming, ultra-dense small cell networks, better semiconductor technology, signal polarization and dynamic spectrum access–lot of new spectrum will be required.
Early discussion of which bands in the millimeter wave band (3 GHz to 300 GHz) will happen at this year’s World Radiocommunications Conference.
To give you some idea of what eventually will happen, the regional allocation for mobile services now is about 500 MHz, in total. For 5G, allocations are expected to be in the 10 GHz range. In other words, two orders of magnitude more bandwidth is expected to be allocated, but most of the growth will come from use of small cell architectures.
Some think as much as two orders of magnitude effective spectrum use will come from small cell architectures, about 20 times improvement from additional spectrum and maybe twice as much effective use will come from all the improvements made possible by Moore’s Law.
But there is lots of room for surprise. Some think the present limit of about two bits per Hertz of bandwidth could grow to 10 bits per Hertz or even 30 bits per Hertz, effectively. That would be a stunning advance, indeed.
source: Keysight Technologies