Why do short wavelengths carry a huge amount of data not long?

In summary: If it is too wide, the signal will 'bleed' into adjacent channels and the data will be distorted or lost.
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Seneka
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Why do short wavelengths carry a huge amount of data not long?

I think this is because short wavelengths are faster o_O
 
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The way electromagnetic waves carry data is by altering the base wave. So, you can bump the amplitude of the wave a bit, or the frequency, or the phase, and so forth. Every time you do that, though, you are causing the original wave to occupy a finite band of frequencies instead of just one single frequency. (Only a pure sinusoidal "carrier wave" wave that never changes has one single frequency. The moment you change the wave from a pure sine wave you cause it to occupy a spread of frequencies.) The width of that band is called the signal's bandwidth. So, for example, your cell phone operating at nominal frequency around 2 GHz will actually produce a band of frequencies about 20 MHz wide, so for example all frequencies between 1.990 GHz and 2.010 GHz.

Very roughly speaking, the bandwidth is controlled by how many times per second you wiggle the base signal. You get a bandwidth of 20 MHz if you wiggle it up to 20 million times per second. If you wiggled it slower, you would get a smaller bandwidth, and if you wiggled it faster, you would get a larger bandwidth. So the bandwidth is directly connected to how fast you can transmit data: if you want to transmit 10 million bits/s, you need a bandwidth that is very roughly 10 MHz (this is a crude analysis).

Now here comes the crucial point: for practical (and legal) reasons, the bandwidth can't be too different from the base frequency. 1-2% or less is typical. Past that point, it's very hard to design sensitive radio detectors, and you also have the problem of adjacent channels not "staying in their lane" so they don't interfere with each other.

So for a 2 GHz signal, you can have a 20 MHz bandwidth (which is 1% of the base frequency). But if you are operating on the older cell phone frequency of 900 MHz, a 1% bandwidth is only 9 MHz, and you can wiggle your signal only about 9 million times per second -- so you can't transmit data as fast. If you are operating at "shortwave" radio frequencies of about 15 MHz, a 1% bandwidth is only 150 kHz, meaning you can wiggle your signal only about 150,000 times per second, which means far slower data speeds.
 
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  • #3
Seneka said:
Why do short wavelengths carry a huge amount of data not long?

I think this is because short wavelengths are faster o_O
The previous answer is very good. I also want to address your last statement. The speed of light is a constant of nature, identically the same for all electromagnetic wavelengths and frequencies.
 
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Seneka said:
Why do short wavelengths carry a huge amount of data not long?

I think this is because short wavelengths are faster o_O
This is a topic that confuses everyone at first because the terms are strange and used in unfamiliar ways.
Your question would be better phrased in terms of the Frequency rather than Wavelength.
Frequency = c/Wavelength
So, when you say "faster" you really mean "higher frequency" not higher speed. High frequency signals can carry more information than low frequency signals.
If you read the post by @Christopher Grayce you will see that there are two 'frequencies' involved with signalling; there is the 'carrier' frequency (or channel frequency) and there is the Bandwidth of the signal, which relates to its information carrying capacity or range of frequencies used in the signal.
If you are carrying a signal down a wire, where it won't interfere with other signals, you can use the whole of the available frequency range for just one signal. If you want to carry multiple signals in the same wire or through space, you need to have a structure of channels so no one uses the same range frequencies.
The Bandwidth of the signal on a channel will need to be narrow enough for it to fit into the space between the assigned channel frequencies.
 

Related to Why do short wavelengths carry a huge amount of data not long?

1. Why do short wavelengths carry a huge amount of data compared to long wavelengths?

Short wavelengths carry a larger amount of data because they have a higher frequency, meaning they oscillate more times per second. This allows for more data to be transmitted in a shorter amount of time.

2. How does the frequency of a wavelength affect the amount of data it can carry?

The higher the frequency of a wavelength, the more data it can carry. This is because higher frequencies have shorter wavelengths, meaning more cycles can occur in a given time period, allowing for more data to be transmitted.

3. Is there a limit to how much data can be carried by short wavelengths?

There is no physical limit to the amount of data that can be carried by short wavelengths. However, there may be practical limitations based on the technology and equipment used for transmission and reception.

4. Can long wavelengths also carry a large amount of data?

While long wavelengths may not be able to carry as much data as short wavelengths, they can still carry a significant amount. This is because they have a lower frequency and can still transmit data, just at a slower rate compared to short wavelengths.

5. How does the size of a wavelength affect its ability to carry data?

The size of a wavelength does not directly affect its ability to carry data. However, as mentioned before, shorter wavelengths have a higher frequency and can transmit data faster, making them more efficient for carrying a larger amount of data in a shorter amount of time.

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