Extended Algorithms for Sample Rate Conversion

The idea of software radio (SWR) implies the capability of changing the air-interface just by down-loading the respective software. Since analog components (e.g., for prefiltering and digitization) are difficult to parameterize these tasks have to be moved to the digital domain, or have to be done in a standard independent way. In such receivers the task of sample rate conversion (SRC) is essential and has to be performed in an adaptable manner. Polynomial filters are a very suitable choice for sample rate conversion. Since the support (length) of the filter determines the effort and costs implementing this filter, minimizing the support is an important task. It will be shown that using a more general approach to interpolation leads to filters with minimal support for a given accuracy. This results in a considerable reduction of the effort.

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