Howtosignalprocessing
- What is the difference between Filtfilt and filter?
- What is forward backward filtering?
- What does Filtfilt function do in Matlab?
- What are B and A in filter function in Matlab?
What is the difference between Filtfilt and filter?
You can see that although filter() and filtfilt() both remove the high frequency noise, the use of filter() introduces significant phase delay. filtfilt() has zero phase delay. Further, at t=0, the output of filter() starts at 0, whereas the output of filtfilt() has matched the initial conditions exactly 2.
What is forward backward filtering?
Forward-backward filters (Butterworth or other) are non-causal and IIR (infinite impulse response). In other words, the output at each time depends in part on future values of the input, and the response to an impulse extends infinitely far into the future as well as the past.
What does Filtfilt function do in Matlab?
Description. y = filtfilt( b , a , x ) performs zero-phase digital filtering by processing the input data x in both the forward and reverse directions. After filtering the data in the forward direction, the function reverses the filtered sequence and runs it back through the filter.
What are B and A in filter function in Matlab?
In this equation, a and b are vectors of coefficients of the filter, Na is the feedback filter order, and Nb is the feedforward filter order. n is the index of the current element of x. The output y(n) is a linear combination of the current and previous elements of x and y.
