필터 지우기
필터 지우기

delay and sum beamforming

조회 수: 51 (최근 30일)
Dhananjay Singh
Dhananjay Singh 2019년 3월 18일
댓글: Sazid Hasan 2021년 6월 1일
I am making a program to acheive delay and sum beamforming,
I looked for examples of this online and found one relatable. The code is given below. When i run the program i get this error
%% Examples on delay-and-sum response for different arrays and input signals
%% 1D-array case
% Create vectors of x- and y-coordinates of microphone positions
xPos = -0.8:0.2:0.8; % 1xP vector of x-positions [m]
yPos = zeros(1, numel(xPos)); % 1xP vector of y-positions [m]
zPos = zeros(1, numel(xPos));
elementWeights = ones(1, numel(xPos))/numel(xPos); % 1xP vector of weightings
% Define arriving angles and frequency of input signals
thetaArrivalAngles = [-30 10]; % degrees
phiArrivalAngles = [0 0]; % degrees
f = 800; % [Hz]
c = 340; % [m/s]
fs = 44.1e3; % [Hz]
% Define array scanning angles (1D, so phi = 0)
thetaScanAngles = -90:0.1:90; % degrees
phiScanAngles = 0; % degrees
% Create input signal
inputSignal = createSignal(xPos, yPos, zPos, f, c, fs, thetaArrivalAngles, phiArrivalAngles);
% Create steering vector/matrix
e = steeringVector(xPos, yPos, zPos, f, c, thetaScanAngles, phiScanAngles);
% Create cross spectral matrix
R = crossSpectralMatrix(inputSignal);
% Calculate delay-and-sum steered response
S = steeredResponseDelayAndSum(R, e, elementWeights);
%Normalise spectrum
spectrumNormalized = abs(S)/max(abs(S));
%Convert to decibel
spectrumLog = 10*log10(spectrumNormalized);
%Plot array
fig1 = figure;
fig1.Color = 'w';
ax = axes('Parent', fig1);
scatter(ax, xPos, yPos, 20, 'filled')
axis(ax, 'square')
ax.XLim = [-1 1];
ax.YLim = [-1 1];
grid(ax, 'on')
title(ax, 'Microphone positions')
%Plot steered response with indicator lines
fig2 = figure;
fig2.Color = 'w';
ax = axes('Parent', fig2);
plot(ax, thetaScanAngles, spectrumLog)
grid(ax, 'on')
ax.XLim = [thetaScanAngles(1) thetaScanAngles(end)];
for j=1:numel(thetaArrivalAngles)
indx = find(thetaScanAngles >= thetaArrivalAngles(j), 1);
line(ax, [thetaScanAngles(indx) thetaScanAngles(indx)], ax.YLim,'LineWidth', 1, 'Color', 'r', 'LineStyle', '--');
end
xlabel(ax, '\theta')
ylabel(ax, 'dB')
  댓글 수: 3
Dhananjay Singh
Dhananjay Singh 2019년 3월 18일
function signalTotal = createSignal(xPos, yPos, zPos, f, c, fs, thetaArrivalAngles, phiArrivalAngles, amplitudes, nSamples, coherence)
%createSignal - create input signal to an array of microphones
%
%Creates the input signal to an array of microphones based on the position
%in space of the microphones and the arrival angle and amplitude of the individual sources
%signalTotal = createSignal(xPos, yPos, zPos, f, c, fs, thetaArrivalAngles, phiArrivalAngles, amplitudes, nSamples, coherence)
%IN
%xPos - 1xP vector of x-positions [m]
%yPos - 1xP vector of y-positions [m]
%zPos - 1xP vector of z-positions [m]
%f - Wave frequency [Hz]
%c - Speed of sound in [m/s]
%fs - Sampling frequency in [Hz]
%thetaArrivalAngles - 1xM vector of theta arrival angles for sources
%phiArrivalAngles - 1xM vector of phi arrival angles for sources
%amplitudes - 1xM vector of amplitudes of sources
%nSamples - Number of samples to be used in the calculations
%coherence - Boolean to make input signals coherent or not
%
%OUT
%signalTotal - PxN matrix of input signal to individual sensors
if ~exist('coherence', 'var')
coherence = false;
rng('default')
end
if ~exist('nSamples', 'var')
nSamples = 1e3;
end
if ~exist('amplitudes', 'var')
amplitudes = zeros(1,numel(xPos));
end
if ~isvector(xPos)
error('X-positions of array elements must be a 1xP vector where P is number of elements')
end
if ~isvector(yPos)
error('Y-positions of array elements must be a 1xP vector where P is number of elements')
end
if ~isvector(zPos)
error('Z-positions of array elements must be a 1xP vector where P is number of elements')
end
T = nSamples/fs;
t = 0:1/fs:T-1/fs;
signalTotal = 0;
for k = 1:numel(thetaArrivalAngles)
%Create signal hitting the array
doa = squeeze(steeringVector(xPos, yPos, zPos, f, c, thetaArrivalAngles(k), phiArrivalAngles(k)));
%Add random phase to make signals incoherent
if coherence
signal = 10^(amplitudes(k)/20)*doa*exp(1j*2*pi*f*t);
else
signal = 10^(amplitudes(k)/20)*doa*exp(1j*2*pi*(f*t+randn(1, nSamples)));
end
%Total signal equals sum of individual signals
signalTotal = signalTotal + signal;
end
Sazid Hasan
Sazid Hasan 2021년 6월 1일
Is that problem solved?

댓글을 달려면 로그인하십시오.

답변 (0개)

카테고리

Help CenterFile Exchange에서 Signal Radiation and Collection에 대해 자세히 알아보기

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by