DIGITAL FILTERBANKS BASED ON RESAMPLING
Consider the two-band filterbank shown below:


where f(n) and g(n) are complementary low pass and high pass filters:

• To achieve perfect reconstruction of x(n), we need ideal filters, which are not realizable.
  
  
• Is it possible to build a filterbank that has perfect reconstruction?
  
  
• Why might such a filterbank be useful for speech recognition?