Shannon's Therorem (paraphrased) states that |
This is probably the most important concept in DSP. |
It also implies that no frequency above half the sampling rate can be represented. |
This comes into play when we want to synthesize signals in the digital domain. |
Some signal processing techniques can generate new frequency components which violate this principle. |
Common sampling frequencies are 44100Hz (Audio CD) and 48000Hz (Digital Audio Tape). |
There is also a move towards higher sampling rates like 88100Hz (SACD?) 96000Hz (Audio DVD) and even 192000Hz. |