Signals From Noise: Constructing SINCk Decimators With A Subtractor
The SINCK decimator is a widely used digital FIR filter. Limitations in its performance are made up by its ease of construction as it does not require the use of a multiplier to generate weighted samples to accumulate. Traditionally, this is done with a digital adder to construct accumulators (Σ) and a digital subtractor to generate differences (Δ). This TechNote will show a method to construct a decimator that requires only a subtractor for all arithmetic operations. It can easily be constructed with programmable logic.
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