This example demonstrates how to use the Altera® DSP Builder Advanced Blockset (DSPB-AB) to implement a multi-channel sample rate conversion filter based on a Farrow structure.
Sample rate conversion has a wide range of applications such as wireless communications, medical imaging, and military applications. Instead of implementing polyphase decomposition, the Farrow resampling filter uses low-order polynomials to realize the same functionality, thus results in significant logic savings. It is particularly efficient for processing multiple channels or multiple parallel data paths, where all channels or data paths require the same set of filter coefficients.
In this example, we build a Farrow sample rate conversion filter using DSPB-AB primitive blocks. In particular, we demonstrate how to take advantage of the folding feature of the DSPB-AB. The folding feature of the DSPB-AB automatically realizes resource sharing and hardware re-use based on user-specified system parameters.
The functional block diagram of a Farrow filter is shown in Figure 1. All modules are designed using primitive blocks in DSPB-AB.
Figure 1. Farrow Filter Block Diagram