Why Frequency is important?
To really understand that, we must introduce one of the coolest mathematical ideas ever (seriously), and that is 'Fourier Analysis'.
One of the Fundamental Secrets of the Universe
All waveforms, no matter what you scribble or observe in the universe, are actually just the sum of simple sinusoids of different frequencies.
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| Fig-1 |
The first component is a sinusoidal wave with period T=6.28 (2*pi) and amplitude 0.3, as shown in Figure 2.
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| Fig-2 |
The second frequency will have a period half as long as the first (twice the frequency). The second component is shown on the left in Figure 3, along with the sum of the first two frequencies compared to the original waveform.
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| fig-3 |
The third frequency component is 3 times the frequency as the first.
Finally, adding in the fourth frequency component, we get the original waveform, shown in Figure
However, since every piece of information in the universe can be decomposed into sine and cosine components of varying frequencies, we always discuss antennas in terms of the wavelength it operates at or the frequency we are using.
As a further consequence of this, the power an antenna can transmit is divided into frequency regions, or frequency bands.