k-Wave User Forum » Topic: How to define the best sensor.directivity

k-Wave User Forum » Topic: How to define the best sensor.directivity_size for 2D simulation? http://www.k-wave.org/forum/topic/how-to-define-the-best-sensordirectivity_size-for-2d-simulation Support for the k-Wave MATLAB toolbox en-US Tue, 12 May 2026 23:40:29 +0000 http://bbpress.org/?v=1.0.2 <![CDATA[Search]]> q http://www.k-wave.org/forum/search.php Bradley Treeby on "How to define the best sensor.directivity_size for 2D simulation?" http://www.k-wave.org/forum/topic/how-to-define-the-best-sensordirectivity_size-for-2d-simulation#post-8766 Sun, 21 May 2023 13:49:23 +0000 Bradley Treeby 8766@http://www.k-wave.org/forum/ This is the physical size of the detecting element. There is some discussion in <a href="http://www.k-wave.org/papers/2010-Cox-SPIE.pdf">this paper</a>. hyaocai on "How to define the best sensor.directivity_size for 2D simulation?" http://www.k-wave.org/forum/topic/how-to-define-the-best-sensordirectivity_size-for-2d-simulation#post-8733 Fri, 24 Mar 2023 23:22:20 +0000 hyaocai 8733@http://www.k-wave.org/forum/ Dear Ben and Brad, I'm currently doing 2D simulation on k-wave, an professional tool for photoacoustics.I notice the simulation results vary based on different 'sensor.directivity_size' parameters. Could you please explain in more detail how to define the best sensor.directivity_size? To make my question specific, I post my model below: % define the properties of the propagation medium medium.sound_speed = 1500; % [m/s] PML_size = 10; Nx = 320 - 2 * PML_size; Ny = 520 - 2 * PML_size; dx = 0.0005; % m dy = dx; kgrid = kWaveGrid(Nx, dx, Ny, dy); % create the time array kgrid.makeTime(medium.sound_speed); source.p0 = zeros(Nx,Ny); source.p0(100,100) = 100; sensor.mask = zeros(Nx, Ny); sensor.mask(39:262,1) = 1; % define the angle of max directivity for each sensor point: dir_angles = (67.5:45/223:112.5)'/180*pi; % assign to the directivity mask sensor.directivity_angle = zeros(Nx, Ny); sensor.directivity_angle(sensor.mask == 1) = dir_angles; % define the directivity pattern sensor.directivity_pattern = 'pressure'; % define the directivity size sensor.directivity_size = 16 * kgrid.dx; % define the frequency response of the sensor elements center_freq = 0.35e6; % [Hz] bandwidth = 50; % [%] sensor.frequency_response = [center_freq, bandwidth]; % set the input arguements input_args = {'PMLSize', PML_size, 'PMLInside', false, 'PlotPML', false, ... 'Smooth', false, 'DataCast', 'single', 'CartInterp', 'nearest'}; % run the simulation sensor_data = kspaceFirstOrder2D(kgrid, medium, source, sensor, input_args{:});