How to Change Signal Bandwidth: Theoretical Possibilities and Effects Explained

[amanno]

Hey guys,

So this is entirely theoretical and I am just curious if its possible and how it could be done. But how can you go about changing the bandwidth of a particular signal?

So a lot of times we have a signal at a given frequency, and there might be a little bit of aliasing into other channels (if not filtered properly) correct? But what if I wanted that to happen, what if I wanted to make a certain signal cover (or transmit) over an entire band? Theoretically is that possible without some side effect? What is the downside of increased bandwidth?

Thanks

 

[Baluncore]

Spread spectrum would meet your requirement.
http://en.wikipedia.org/wiki/Spread_spectrum

You could use either direct sequence or frequency hopping to broaden a signal, depending on what you want to achieve.
The only downside would be the complexity of synchronisation, but there are very many advantages.

There are restrictions on bandwidth in the radio spectrum. SS is not used below 400 MHz.
Below 400MHz wide band FM is a broadening technique that has conversion gain benefits.