Howtosignalprocessing
- What is polyphase decomposition explain in detail?
- Why polyphase filter is used?
- How does a polyphase filter work?
- How does polyphase filtering save computation in decimation filter?
What is polyphase decomposition explain in detail?
Polyphase Decomposition. The multirate operations of decimation and interpolation that were introduced. in the previous section will now be used to decompose any system function. H(z) into its polyphase representation. Consider a discrete–time LTI system.
Why polyphase filter is used?
The polyphase FIR filter realization can provide advantages in computational efficiency when used for decimation or interpolation of discrete time signals.
How does a polyphase filter work?
A polyphase filterbank uses the DFT (discrete fourier transform) to modulate (move in frequency) a prototype filter and perform summation, effectively returning multiple bands of decimated and filtered time-domain data from the DFT stage. The DFT operation is typically performed using the FFT (fast fourier transform).
How does polyphase filtering save computation in decimation filter?
The concept behind a decimating polyphase filter is to avoid wasted computation due to the discarding of samples. Decimation is the process of low-pass filtering (LPF) followed by downsampling, shown in Figure 1. The LPF minimizes aliasing coming from the discarding of samples from downsampling.
