Need info on Digital signal processing applications on handphones?

Question

Simplest layman language if possible

Answer 1

when you want simple and clear answer you have to ask clear questions.but based on what i understand the answer is this:
digital signal processing deals with fourier transform.this transform deals with the same thing but in frequency instead of time.you can do processes such as deleting noises that you know their frequency.amplifing frequencies that you think are good to ear.they are understood by these transform and are done by some electronic circuits.

Answer 2

DSP deals with any signal processing in the discrete domain. While Fourier transform are covered, they are not the only thing DSP involves.

By handphones, I'll assume you mean cell phones. DSP architectures are made in hardware to decode your cell phone signal.