k-Wave User Forum » Topic: get the sensor

k-Wave User Forum » Topic: get the sensor_data in NAN http://www.k-wave.org/forum/topic/get-the-sensor_data-in-nan Support for the k-Wave MATLAB toolbox en-US Fri, 15 May 2026 19:44:02 +0000 http://bbpress.org/?v=1.0.2 <![CDATA[Search]]> q http://www.k-wave.org/forum/search.php luxuriance on "get the sensor_data in NAN" http://www.k-wave.org/forum/topic/get-the-sensor_data-in-nan#post-6184 Fri, 03 Nov 2017 14:22:43 +0000 luxuriance 6184@http://www.k-wave.org/forum/ I get the wrong place. check the neper2db's units. luxuriance on "get the sensor_data in NAN" http://www.k-wave.org/forum/topic/get-the-sensor_data-in-nan#post-6183 Fri, 03 Nov 2017 13:44:50 +0000 luxuriance 6183@http://www.k-wave.org/forum/ Hello, I am stuck in the dilemma. the sensor_data is always get nan. I don't know where I did wrong. I want to construct a space with a little ball. The outside is muscle, the ball is used in kidney's material. Using one sender with three receivers. But I get the wrong answer all along.Here is my code. Thanks very much. %% clear clear; clc; %% Creat Grid Grid_Accuracy=1e3 x=0.05 y=0.05 z=0.05 [kgrid,Nx,dx,Ny,dy,Nz,dz]=CreatGrid(Grid_Accuracy,x,y,z) %% define signal fc=5e6 Tm = 0.2e-4; % pulse duration [s] tau = 0.1e-4; % shaping factor for the pulse [s] source_signal=cp0201_waveform(fc,Tm,tau) %% define kgrid.t_array dt=1/fc time_end=5*Tm kgrid.t_array=0:dt:time_end %% coefficient speed_muscle=1629 ;%(1529-1629); density_muscle=1056 ;%(1038-1056); alpha_coeff_muscle=neper2db(0.54/4.3); %alpha=0.54@4.3Mhz 10^2 neper m^-1, a*f^b, this is a alpha_power_muscle=1; %b BonA_muscle=7.4; %(7.4-8.1) speed_kidney=1580 ;%(1560-1580) density_kidney=1050; alpha_coeff_kidney=neper2db(0.23/2); %alpha=0.23@2Mhz, a*f^b, this is a alpha_power_kidney=1; %b BonA_kidney=5.8; %(5.8-9.0) %% ball center cx=x/2*Grid_Accuracy; cy=y/2*Grid_Accuracy; cz=z/2*Grid_Accuracy; %% initial medium coefficents medium.alpha_mode='no_dispersion'; medium.sound_speed=speed_muscle*ones(Nx,Ny,Nz); medium.density=density_muscle*ones(Nx,Ny,Nz); medium.alpha_coeff =alpha_coeff_muscle*ones(Nx,Ny,Nz); medium.alpha_power=alpha_power_muscle; medium.BonA=BonA_muscle*ones(Nx,Ny,Nz); %% define ball medium for i=1:1:Nx for j=1:1:Ny for k=1:1:Nz d_ball=((i-cx)^2+(j-cy)^2+(k-cz)^2)^(1/2); if d_ball <= 0.002*Grid_Accuracy medium.sound_speed(i,j,k)=speed_kidney; medium.density(i,j,k)=density_kidney; medium.alpha_coeff(i,j,k)=alpha_coeff_kidney; medium.BonA(i,j,k)=BonA_kidney; end end end end %% define source and sensor source.p_mask=zeros(Nx,Ny,Nz); sensor.mask=zeros(Nx,Ny,Nz); sx=round(Nx/2); sz=sx; sy=1; source.p_mask(sx,sy,sz)=1; sensor_circle=0.001; sensory1=1; sensory2=1; sensory3=1; sensorx1=round(sensor_circle*Grid_Accuracy+sx); sensorz1=sz; sensorx2=round(sx-sensor_circle*Grid_Accuracy/2); sensorz2=round(sz-sensor_circle*Grid_Accuracy*3^(1/2)/2); sensorx3=round(sx+sensor_circle*Grid_Accuracy/2); sensorz3=round(sz+sensor_circle*Grid_Accuracy*3^(1/2)/2); sensor.mask(sensorx1,sensory1,sensorz1)=1 sensor.mask(sensorx2,sensory2,sensorz2)=1 sensor.mask(sensorx3,sensory3,sensorz3)=1 %% define sensor.record sensor.record={'p','u','I'}; %% define signal %source.p(1,:)=source_signal source.p(1,:)=[1,1,1]; %% send sensor_data=kspaceFirstOrder3D(kgrid,medium,source,sensor,'PlotLayout',true);%,'DataCast','gpuArray-single','PlotPML',true %% plot [t_sc,scale,prefix]=scaleSI(max(kgrid.t_array(:))); figure() subplot(2,1,1) plot(source.p,'k-') xlabel(strcat('Time [',prefix,'s]')); ylabel('Signal Amplitude') axis tight; title('Input Pressure Signal'); subplot(2,1,2) plot(sensor_data.p(1,:),'r-'); xlabel(strcat('Time [',prefix,'s]')); ylabel('Signal Amplitude') axis tight; title('Sensor Pressure Signal'); function [kgrid,Nx,dx,Ny,dy,Nz,dz]=CreatGrid(Grid_Accuracy,x,y,z) Nx=Grid_Accuracy*x Ny=y*Grid_Accuracy Nz=z*Grid_Accuracy dx=1/Grid_Accuracy dy=dx dz=dx kgrid=kWaveGrid(Nx,dx,Ny,dy,Nz,dz) density_muscle=1056 %(1038-1056) speed_muscle=1629 %(1529-1629) alpha_coeffi_muscle=neper2db(0.125) % alpha=0.54@4.3Mhz (alpha=a*f^b,alpha: neper m^-1,,,0.54/4.3) alpha_power_muscle=1 BonA_muscle=7.4 %(7.4-8.1 B/A) desity_kidney=1050 speed_kidney=1580 %(1560-1580) alpha_coef_kidney=neper2db(0.23/2) % alpha=0.23@2MHz alpha_power_kidney=1 BonA_kidney=5.8 %(5.8-9.0) end function [w0]= cp0201_waveform(fc,Tm,tau); % ------------------------------------ % Step One - Pulse Waveform Generation % ------------------------------------ % fc = 50e6; %sample frequency % Tm = 0.2e-5; % pulse duration [s] % tau = 0.1e-5; % shaping factor for the pulse [s] % dPPM = 0.5e-5; % time shift introduced by the PPM [s] dt = 1 / fc; % reference sampling period OVER = floor(Tm*fc); % number of samples representing % the pulse e = mod(OVER,2); kbk = floor(OVER/2); tmp = linspace(dt,Tm/2,kbk); s = (1-4.*pi.*((tmp./tau).^2)).* ... exp(-2.*pi.*((tmp./tau).^2)); % figure; % plot(s); if e % OVER is odd for k=1:length(s) y(kbk+1)=1; y(kbk+1+k)=s(k); y(kbk+1-k)=s(k); end else % OVER is even for k=1:length(s) y(kbk+k)=s(k); y(kbk+1-k)=s(k); end end % figure; % plot(y); E = sum((y.^2).*dt); % pulse energy w0 = y ./ (E^0.5); % energy normalization