Data communications is based upon the relationship discovered years ago by Claude Shannon and Robert Hartley of Bell Labs. It says:
C = B Χ log2(1 + S/N)
C = maximum channel capacity in bits/second,
B = channel bandwidth in hertz,
S = signal power in watts, and
N = noise power in watts.
In conventional data communications and wireless applications, the bandwidth is fixed. So, higher speeds can only be achieved with higher signal power or multiple symbol transmission schemes. Data rate scales as the logarithm of the power level.
However, note that data rate scales linearly with bandwidth. This gives an ultrawideband system the highest data-rate capability of all wireless techniques.