Filter Bank Article Index for
Filter
Website Links For
Filter
 

Information About

Filter Bank




The filter bank serves to isolate different frequency components in a Signal . This is useful because for most applications some frequencies are more important than others. For example these important frequencies can be coded with a fine resolution. Small differences at these frequencies are significant and a Coding scheme that preserves these differences must be used. On the other hand, less important frequencies do not have to be exact. A coarser coding scheme can be used, even though some of the finer details will be lost in the coding.

The Vocoder uses a filter bank to determine the amplitude information of the subbands of a modulator signal (such as a voice) and uses them to control the amplitude of the subbands of a carrier signal (such as the output of a guitar or synthesizer), thus imposing the dynamic characteristics of the modulator on the carrier.

If the filters are combined with Downsampling or Upsampling then it is useful to represent that combination by a Polyphase Matrix .
With the Polyphase Matrix you easily answer the question for the Perfect Reconstruction property of a filter bank.


SEE ALSO