HJR-DSP: Several filter designs

MATLAB and CSS Two software are required to do the filter

MATLAB is responsible for generating a set of units of Impulse response array H[n]

The C language of CSS is responsible for the system response function based on the input function X[n] and the generated unit impulse response operation Y[n]

i.e. X[n] and H[n] y[n]

First, the filter, common low-pass, high-pass, band-pass, with resistance

Low-pass: Low frequency can pass, Qualcomm: High frequency can pass, Band pass: A certain frequency can pass, with resistance: a certain frequency can not pass

Also divided into Fir and IIR, one is a finite impulse response, an infinite impulse response

First write Matlab program, there are several parameters, high-pass and low-pass have WP,WS,WC, band-pass and band-stop with WP1,WP2,WS1,WS2,WC1,WC2 because of band-pass and band-resistance

is the pass band (pass) cutoff frequency, the cutoff frequency of the band (stop), the digital field cutoff frequency

wherein the WC is a reaction system characteristics of the value, according to WP and WS, and finally brought into the MATLAB self-contained function, do not control his actual meaning

If it is high-pass: The filtered frequency is retained greater than the pass-band cutoff frequency value, filter out less than the resistance band cutoff frequency value

Low pass: retains a value less than the cut-off frequency of the pass band and filters out values greater than the cutoff frequency of the resistance band

So, Qualcomm Wp>ws, low-pass WP<WS

There will be a section that does not belong to the pass or the band of Resistance.

For example why Qualcomm is not higher than 1000-pass, less than 1000 resistance, but higher than 1000 pass below 950 resistance, the middle 50 is because of attenuation, band-band Resistance also has such a section

Band pass: reserved greater than WP less than WS, filter out less than WP more than the WS frequency value

Band Resistance: Keep Less than WP greater than WS, filter out values larger than WP less than WS-Frequency

That is when

WP>WS: Qualcomm

WP<WS: Low-pass

Wp,ws is two Yuan vector

wp=[0.2 0.7] ws[0.1 0.8]: Band-Pass

wp=[0.1 0.8] ws[0.2 0.7]: band resistance