EEN502 Project 1 Part 4 (B)

Page history last edited by Leon D\'Angio 16 years, 7 months ago

Description

The circumstances in Part 1 and Part 3 are re-examined with the observer now being a human listening binaurally.

MatLab Code (Part 2)

M-File :::::: Proj1p4b.m

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%User Input

disp('The sound source is a tone generated by the linear combination of three tones.');

f01=input('Enter the 1st frequency: ');

f02=input('Enter the 2nd frequency: ');

f03=input('Enter the 3rd frequency: ');

disp('The tone has an inate loudness or amplitude, a.');

a=input('Enter the amplitude of the signal: ');

disp('The sound source is moving at a constant velocity, v.');

v=input('Enter the velocity of the sound source: ');

disp('The sound source begins at a distance, d, from the observer.');

d=input('Enter the initial distance of the sound source: ');

disp('The observer is a distance, r, from the source`s trajectory.');

r=input('Enter the observer`s distance from the trajectory: ');

%Constants and Initialization

fs=8000; %Sampling Rate

c=344; %Speed of Sound in air

t=0:1/fs:2*(d/v); %X-Axis, Time, seconds

fo1R=zeros(1,length(t)); %Initialization vector for perceived frequency

fo2R=zeros(1,length(t));

fo3R=zeros(1,length(t));

fo1L=zeros(1,length(t));

fo2L=zeros(1,length(t));

fo3L=zeros(1,length(t));

ioR=zeros(1,length(t)); %Initialization vector for perceived loudness

ioL=zeros(1,length(t)); %Initialization vector for perceived loudness

voR=zeros(1,length(t)); %Initialization vector for relative velocity

voL=zeros(1,length(t)); %Initialization vector for relative velocity

angoR=zeros(1,length(t)); %Initialization vectory for angle

angoL=zeros(1,length(t)); %Initialization vectory for angle

%Doppler Calculation Algorithm

for i=1:length(t)

dt=t(i)*v;

diR=abs(d-dt-(.017/2));

diL=abs(d-dt+(.017/2));

if i<=(d/v)*fs

angoR(i)=atan(-r/diR);

angoL(i)=atan(-r/diL);

voR(i)=v*cos(angoR(i));

voL(i)=v*cos(angoL(i));

fo1R(i)=f01*(c/(c-voR(i)));

fo2R(i)=f02*(c/(c-voR(i)));

fo3R(i)=f03*(c/(c-voR(i)));

fo1L(i)=f01*(c/(c-voL(i)));

fo2L(i)=f02*(c/(c-voL(i)));

fo3L(i)=f03*(c/(c-voL(i)));

end

if i>(d/v)*fs

angoR(i)=atan(r/diR);

angoL(i)=atan(r/diL);

voR(i)=v*cos(angoR(i));

voL(i)=v*cos(angoL(i));

fo1R(i)=f01*(c/(c+voR(i)));

fo2R(i)=f02*(c/(c+voR(i)));

fo3R(i)=f03*(c/(c+voR(i)));

fo1L(i)=f01*(c/(c+voL(i)));

fo2L(i)=f02*(c/(c+voL(i)));

fo3L(i)=f03*(c/(c+voL(i)));

end

hypR(i)=sqrt(r^2 + diR^2);

hypL(i)=sqrt(r^2 + diL^2);

ioR(i)=a/hypR(i);

ioL(i)=a/hypL(i);

end

s1R=ioR.*sin(2*pi*fo1R.*t);

s2R=ioR.*sin(2*pi*fo2R.*t);

s3R=ioR.*sin(2*pi*fo3R.*t);

s1L=ioL.*sin(2*pi*fo1L.*t);

s2L=ioL.*sin(2*pi*fo2L.*t);

s3L=ioL.*sin(2*pi*fo3L.*t);

sR=(1/3)*(s1R+s2R+s3R);

sL=(1/3)*(s1L+s2L+s3L);

sR=sR';

sL=sL';

s=[sR, sL];

%Plots

subplot(321); plot(t, fo1R); title('Observed Frequency 1 (Right Ear)');