k-Wave User Forum » Topic: Determining Frequency

k-Wave User Forum » Topic: Determining Frequency http://www.k-wave.org/forum/topic/determining-frequency Support for the k-Wave MATLAB toolbox en-US Tue, 12 May 2026 23:36:43 +0000 http://bbpress.org/?v=1.0.2 <![CDATA[Search]]> q http://www.k-wave.org/forum/search.php bencox on "Determining Frequency" http://www.k-wave.org/forum/topic/determining-frequency#post-8516 Mon, 25 Apr 2022 19:37:04 +0000 bencox 8516@http://www.k-wave.org/forum/ You are setting an initial pressure with <code>source.p0</code> whereas you want a time-varying source <code>source.p</code>, which you have commented out. hasansss on "Determining Frequency" http://www.k-wave.org/forum/topic/determining-frequency#post-8493 Fri, 01 Apr 2022 11:52:39 +0000 hasansss 8493@http://www.k-wave.org/forum/ Hello, I would like to change my frequency in k-Wave but ı could not change it by using the below codes. Graphs remain same when I changed the values . How can it be changed? Do you have any suggestions? Codes that I used % define properties of the input signal source_strength = 10e6; % [MPa] tone_burst_freq = 0.5e6; % [Hz] tone_burst_cycles = 5000; kgrid.dt = 1000; ** I tried to change these four values but graph remain same All my code clc clear % 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 = 50 - 2*PML_X_SIZE; % [grid points] Ny = 50 - 2*PML_Y_SIZE; % [grid points] Nz = 50 - 2*PML_Z_SIZE; % [grid points] dx = 0.1e-3; % grid point spacing in the x direction [m] dy = 0.1e-3; % grid point spacing in the y direction [m] dz = 0.1e-3; % grid point spacing in the z direction [m] kgrid = kWaveGrid(Nx, dx, Ny, dy, Nz, dz); % define the properties of the propagation medium medium.sound_speed = 1400* ones(Nx, Ny,Nz); % [m/s] medium.sound_speed(Nx/2:Nx, :,:) = 1600; % [m/s] medium.density = 1 * ones(Nx, Ny,Nz); % [kg/m^3] medium.density(Nx/2:Nx, :, :) = 1; % [kg/m^3] % simulation settings DATA_CAST = 'single'; disc_magnitude = 10; % [Pa] disc_x_pos = 20; % [grid points] disc_y_pos = 3; % [grid points] disc_z_pos = 2; disc_radius = 1; % [grid points] %disc_2 = disc_magnitude * makeDisc(Nx, Ny,Nz ,disc_x_pos, disc_y_pos,disc_z_pos, disc_radius); % create source mask source.p_mask = makeBall(Nx, Ny,Nz ,disc_x_pos, disc_y_pos,disc_z_pos, disc_radius); source.p0 = source.p_mask; % define properties of the input signal source_strength = 10e6; % [MPa] tone_burst_freq = 0.5e6; % [Hz] tone_burst_cycles = 5000; kgrid.dt = 1000; % create the input signal using toneBurst input_signal = toneBurst(1/kgrid.dt, tone_burst_freq, tone_burst_cycles); % 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 = 3; % total number of transducer elements transducer.element_width = 1; % width of each element [grid points/voxels] transducer.element_length = 3; % length of each element [grid points/voxels] transducer.element_spacing = 1; % 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([1, Ny/2 - transducer_width/2, Nz/2 - transducer.element_length/2]); transducer.position = [0.5,0.5,0.5]; % properties used to derive the beamforming delays transducer.sound_speed = 100; % sound speed [m/s] transducer.focus_distance = 25e-3; % focus distance [m] transducer.elevation_focus_distance = 19e-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 = zeros(transducer.number_elements, 1); transducer.active_elements(1:3) = 1; % create the transducer using the defined settings transducer = kWaveTransducer(kgrid, transducer); % print out transducer properties transducer.properties; transducer.plot;