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FIR | Matched Filters

In addition to FIR matched filters, FilterSolutions supports passive, active, and digital IIR matched filters. It is possible, however, to create much more accurate FIR matched filters than those created by other methods.

The distinguishing characteristic of a Matched Filter is the step response approximates a ramp, and the impulse response approximates a pulse. The purpose of the Matched Filter is to maximize the signal to noise ratio and to minimize the probability of undetected errors received from a signal.

FilterSolutions allows the design of a Matched Filter to be determined by setting the rise time of the ramp.

FilterSolutions will automatically set the sample rate to the value needed to create a matched filter with the user defined order and rise time.  The proper use of the matched filter is to set the rise time to be equal to the pulse width of the pulses in a bit stream.

The ideal matched filter step and impulse response is shown below.

Ideal Matched Filter Time Response