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Change emphasis time constant to 750µS

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This commit is contained in:
Geoffrey Merck 2020-04-30 10:26:04 +02:00
parent b2f33fd4d2
commit 69e39e36b0
2 changed files with 14 additions and 11 deletions
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21
Tools/emphasis.txt
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@ -9,21 +9,24 @@ clear all;
clc;
fs = 24000;
timeConstant = 0.00075; %750µS
samplingtime = 1/fs;
% analog prototype
A2 = [1];
B2 = [0.000075 1];
B2 = [timeConstant 1];
% Pre
Ds = tf(B2, A2);
%Ds = tf(B2, A2);
% De
% Ds = tf(A2, B2);
Ds = tf(A2, B2);
Ds = Ds/dcgain(Ds);
% MZT
T1 = 0.000075; % 75us
T1 = timeConstant;
z1 = -exp(-1.0/(fs*T1));
p1 = 1+z1;
@ -37,12 +40,12 @@ b2 = 0;
% swap between a1, b1 to select pre- or de-emphasis
# Pre
Bmzt = [b0 a1 b2]
Amzt = [a0 b1 a2]
% Pre
%Bmzt = [b0 a1 b2]
%Amzt = [a0 b1 a2]
% De
% Bmzt = [b0 b1 b2]
% Amzt = [a0 a1 a2]
Bmzt = [b0 b1 b2]
Amzt = [a0 a1 a2]
DzMZT = tf(Amzt, Bmzt, samplingtime);
DzMZT = DzMZT/dcgain(DzMZT);