k-Wave User Forum » Topic: concave and linear probe

k-Wave User Forum » Topic: concave and linear probe http://www.k-wave.org/forum/topic/concave-and-linear-probe Support for the k-Wave MATLAB toolbox en-US Wed, 13 May 2026 01:09:38 +0000 http://bbpress.org/?v=1.0.2 <![CDATA[Search]]> q http://www.k-wave.org/forum/search.php Gwansuk on "concave and linear probe" http://www.k-wave.org/forum/topic/concave-and-linear-probe#post-6969 Wed, 10 Jul 2019 22:29:31 +0000 Gwansuk 6969@http://www.k-wave.org/forum/ Thank you, Brad. It Works~! Best Gwansuk Bradley Treeby on "concave and linear probe" http://www.k-wave.org/forum/topic/concave-and-linear-probe#post-6966 Wed, 10 Jul 2019 16:09:04 +0000 Bradley Treeby 6966@http://www.k-wave.org/forum/ Hi Gwansuk , The values for <code>transducer.focus_distance</code> and <code>transducer.elevation_focus_distance</code> can't can't be set to zero. If you change them to, e.g., 1e-3, your simulation runs. If you want the transmit to be unfocused, set them to <code>inf</code>. Brad. Gwansuk on "concave and linear probe" http://www.k-wave.org/forum/topic/concave-and-linear-probe#post-6933 Wed, 26 Jun 2019 18:26:08 +0000 Gwansuk 6933@http://www.k-wave.org/forum/ Hi Brad, is it ok, just post a script here? ---------------------------------------------------------------------------- clear all; close all; clearvars; % simulation settings DATA_CAST = 'single'; % ========================================================================= % DEFINE THE K-WAVE GRID % ========================================================================= % set the size of the perfectly matched layer (PML) PML_X_SIZE = 10; % [grid points] PML_Y_SIZE = 10; % [grid points] PML_Z_SIZE = 10; % [grid points] % set total number of grid points not including the PML Nx = 160 * 2 - 2*PML_X_SIZE; % [grid points] Ny = 190 * 2 - 2*PML_Y_SIZE; % [grid points] Nz = 190 * 2 - 2*PML_Z_SIZE; % [grid points] % calculate the spacing between the grid points dx = 0.2e-3; % [m] dy = dx; % [m] dz = dx; % [m] % create the k-space grid kgrid = kWaveGrid(Nx, dx, Ny, dy, Nz, dz); % ========================================================================= % DEFINE THE MEDIUM PARAMETERS % ========================================================================= % define the properties of the propagation medium c0 = 1540; % [m/s] rho0 = 1000; % [kg/m^3] medium.alpha_coeff = 0.75; % [dB/(MHz^y cm)] medium.alpha_power = 1.5; medium.BonA = 6; % create the time array t_end = 40e-6; kgrid.makeTime(c0, [], t_end); % ========================================================================= % DEFINE THE SOURCE % ========================================================================= % create a concave sensor sphere_offset = 0; % [grid points] diameter = round(64e-3 / dx) +1 ; % [grid points] radius = round(45e-3 / dx); % [grid points] bowl_pos = [1 + sphere_offset, Ny/2, Nz/2]; % [grid points] focus_pos = [Nx/2, Ny/2, Nz/2]; % [grid points] source.p_mask = makeBowl([Nx, Ny, Nz], bowl_pos, radius, diameter, focus_pos) ... - makeBowl([Nx, Ny, Nz], bowl_pos, radius, diameter/2, focus_pos); % define properties of the input signal source_strength = 1e6; % [Pa] tone_burst_freq = 1e6; % [Hz] tone_burst_cycles = 5; % create the input signal using toneBurst source.p = source_strength .* toneBurst(1/kgrid.dt, tone_burst_freq, tone_burst_cycles); % ========================================================================= % DEFINE THE ULTRASOUND TRANSDUCER % ========================================================================= % physical properties of the transducer transducer.number_elements = 128; % total number of transducer elements transducer.element_width = round(0.2e-3 / dx); % width of each element [grid points/voxels] transducer.element_length = round(3.5e-3 / dx); % length of each element [grid points/voxels] transducer.element_spacing = 0; % spacing (kerf width) between the elements [grid points/voxels] transducer.radius = inf; % radius of curvature of the transducer [m] % calculate the width of the transducer in grid points transducer_width = transducer.number_elements * transducer.element_width ... + (transducer.number_elements - 1) * transducer.element_spacing; % use this to position the transducer in the middle of the computational grid transducer.position = round([80, Ny/2 - transducer_width/2, Nz/2 - transducer.element_length/2]); % properties used to derive the beamforming delays transducer.sound_speed = 1540; % sound speed [m/s] transducer.focus_distance = 0e-3; % focus distance [m] transducer.elevation_focus_distance = 0e-3; % focus distance in the elevation plane [m] transducer.steering_angle = 0; % steering angle [degrees] % apodization transducer.transmit_apodization = 'Rectangular'; transducer.receive_apodization = 'Rectangular'; % define the transducer elements that are currently active transducer.active_elements = ones(transducer.number_elements, 1); % create the transducer using the defined settings transducer = kWaveTransducer(kgrid, transducer); % print out transducer properties transducer.properties; % voxelPlot(double(transducer.mask)+double(source.p_mask)); % view(127, 18); % ========================================================================= % DEFINE THE MEDIUM PROPERTIES % ========================================================================= % define a random distribution of scatterers for the medium background_map_mean = 1; background_map_std = 0.008; background_map = background_map_mean + background_map_std * randn([Nx, Ny, Nz]); % define a random distribution of scatterers for the highly scattering % region scattering_map = randn([Nx, Ny, Nz]); scattering_c0 = c0 + 25 + 75 * scattering_map; scattering_c0(scattering_c0 > 1600) = 1600; scattering_c0(scattering_c0 < 1400) = 1400; scattering_rho0 = scattering_c0 / 1.5; % define properties sound_speed_map = c0 * ones(Nx, Ny, Nz) .* background_map; density_map = rho0 * ones(Nx, Ny, Nz) .* background_map; % define a sphere for a highly scattering region radius = 8e-3; x_pos = 32e-3; y_pos = dy * Ny/2; scattering_region1 = makeBall(Nx, Ny, Nz, round(x_pos / dx), round(y_pos / dx), Nz/2, round(radius / dx)); % assign region sound_speed_map(scattering_region1 == 1) = scattering_c0(scattering_region1 == 1); density_map(scattering_region1 == 1) = scattering_rho0(scattering_region1 == 1); % assign to the medium inputs medium.sound_speed = sound_speed_map; medium.density = density_map; % ========================================================================= % RUN THE SIMULATION % ========================================================================= % set the input settings input_args = {'DisplayMask', transducer.active_elements_mask, ... 'PMLInside', false, 'PlotPML', false, 'PMLSize', [PML_X_SIZE, PML_Y_SIZE, PML_Z_SIZE], ... 'DataCast', DATA_CAST, 'PlotScale', [-1/4, 1/4] * source_strength}; % run the simulation sensor_data = kspaceFirstOrder3D(kgrid, medium, source, transducer, input_args{:}); % extract a single scan line from the sensor data using the current % beamforming settings scan_line = transducer.scan_line(sensor_data); % ========================================================================= % VISUALISATION % ========================================================================= % plot the recorded time series figure; stackedPlot(kgrid.t_array * 1e6, sensor_data); xlabel('Time [\mus]'); ylabel('Transducer Element'); title('Recorded Pressure'); scaleFig(1, 1.5); ------------------------------------------------------------------------------ Thanks Gwansuk Bradley Treeby on "concave and linear probe" http://www.k-wave.org/forum/topic/concave-and-linear-probe#post-6930 Wed, 26 Jun 2019 10:44:22 +0000 Bradley Treeby 6930@http://www.k-wave.org/forum/ Hi Gwansuk, It's difficult to say without seeing the rest of the code. Is it possible that you could post a script that reproduces the error? Brad. Gwansuk on "concave and linear probe" http://www.k-wave.org/forum/topic/concave-and-linear-probe#post-6927 Wed, 26 Jun 2019 01:21:21 +0000 Gwansuk 6927@http://www.k-wave.org/forum/ Hi all I am trying to simulate a concave transducer and linear probe. the concave transducer acts as a HIFU transducer and linear probe is used as a receiver. However, the following error occurred during execution. ----------------------------------------------------------------------- Matrix dimensions must agree. Error in kspaceFirstOrder3D (line 978) current_vals = sum(transducer_receive_mask .* sensor_data_buffer, 2); ----------------------------------------------------------------------- I don't think 'transducer_receive_mask' and 'sensor_data_buffer' are not user-defined arrays. I was wondering if you have any information regarding this error. Best, Gwansuk Kang