Each mobile next-generation platform has used distinct blocks of spectrum, which also means 6G will bring additional new frequencies into commercial use. As a practical matter, each successive mobile generation also has used higher frequencies. That is true for 5G and allso was true for 4G.
But there are key implications as additional spectrum is added. Earlier networks used lower-frequency signals that traveled well, if not providing all that much bandwidth. Each next-generation network has relied on higher-frequency signals that do not travel as far, but do support far more bandwidth.
The simple explanation is that potential mobile network bandwidth is directly related to the signal frequency: the lower the frequency, the lower the potential bandwidth; the higher the frequency the higher the potential bandwidth.
The easiest way to explain that relationship is to note that the ability to code information is directly dependent on the oscillation rate. Waves that oscillate fewer times per second can carry less information than waves that oscillate much faster.
source: Millimeter Wave Products
The Shannon Nyquist theorem states that the information rate of any communications channel is twice the bandwidth of the channel. Higher frequencies support wider channels, and therefore greater bandwidth.
A simple coding scheme, for example, might designate the +1 position of the wave as a “one” while the -1 position of the wave might be designated a “zero.” Modern modulation is more complex than that, but fundamental physics still matters. All other things being equal, the more oscillations per second between +1 and -1, the more symbols can be represented.
So when the signal frequency doubles, the information capacity doubles. As you recall, the impact of doubling is logarithmic. In simple binary terms (without radio or modulation changes) If the information capacity of a channel at 800 Mhz is “X,” then capacity at 1600 MHz is 2X.
At 3200 MHz capacity is 4X. At 6.4 GHz capacity is 8X. At 12.8 GHz capacity is 16X At 25.6 GHz capacity is 32X; at 51.2 GHz capacity is 64X.
At 100 GHz capacity is 128X; at 200 GHz 32X.
Modulation and radio architecture also matter. At any given frequency, more complex modulation can boost information capacity by 4X to 128X. More complex radios have the same impact, boosting rates by 2X, 4X, 8X or 16X, depending on the complexity of the array.
Looking at 4G, at any defined frequency, modulation and radio arrays can increase throughput as much as 100 times.
The point is that using higher frequencies means higher data rates, all other things being equal.
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