Bit by Bit Signal Processing is happy to provide tutorials to help customers understand the intended application of its products.
Channelizer_Derivation.pdf -- This presentation derives the math behind the Polyphase Filter Bank channelizer. It assumes a reader is familiar with a number of digital signal processing topics, including theory of mixers, filters, and multirate sampling. From these beginnings, it derives a Polyphase Filter Bank (PFB). It shows the PFB's equivalence to an ideal basebanding filter, which is invaluable in analysis of the PFB. It provides some teasers for more advanced topics, such as performance and applications. These may eventually become additional presentations here at this site.