Numerical analysis of finite word length effects in a multirate filter system

Multirate filters provide efficient filtering compared to traditional linear time-invariant filters. This paper introduces multirate filters and suggests the application of multirate filters for Single Side Band (SSB) demodulation. Implementing the filters in configurable logic provides the opportunity to reduce the bit-width and thereby area usage. The work is split into two; 1) The finite word length effects are analyzed by simulation in SystemC and a word length trade-off is selected. 2) The simulation results are verified by implementation on an Altera Stratix II FPGA EP2S60 kit, using DSP Builder.