http://www.k-wave.org/forum/topic/toneburst-functions-incompatibility-with-lsim-function-matlab Support for the k-Wave MATLAB toolbox en-US Wed, 13 May 2026 15:43:15 +0000 http://bbpress.org/?v=1.0.2 q http://www.k-wave.org/forum/search.php http://www.k-wave.org/forum/topic/toneburst-functions-incompatibility-with-lsim-function-matlab#post-6635 Tue, 06 Nov 2018 21:49:03 +0000 Bradley Treeby 6635@http://www.k-wave.org/forum/ <p>Hi SquaredS,</p> <p>I am not familiar with the <code>Isim</code> function. However, the error message would suggest that adding columns of zero is only correct if the inputs to these channels is zero.</p> <p>Brad. </p> http://www.k-wave.org/forum/topic/toneburst-functions-incompatibility-with-lsim-function-matlab#post-6625 Thu, 01 Nov 2018 01:41:09 +0000 SquaredS 6625@http://www.k-wave.org/forum/ <p>Hello everyone!</p> <p> I am new to the world of Matlab and that of Ultrasounds, so please bear with me if my question does not make any sense. </p> <p>I am trying to simulate the response of an RLC circuit (electrical equivalent of my piezoelectric device) to a burst signal. To generate this signal I am using the k-wave function ToneBurst. To find the voltage on the resistor I am using lsim which exploits state equations. lsim works fine with step, pulse and sine input, but not with ToneBurst (error: "When simulating the response to a specific input signal, the input data U must be a matrix with as many rows as samples in the time vector T, and as many columns as input channels.").</p> <p>So I tried doing this:</p> <p>u = toneBurst(sample_freq, signal_freq,num_cycles);<br /> signal = transpose(u);<br /> rowPad=size(t,1)-size(signal,1);<br /> colPad=0;<br /> signal=padarray(signal,[rowPad,colPad]);<br /> signal(1:rowPad,:)=[];<br /> signal(:,1:colPad)=[];</p> <p>and now it *seems* to be working.</p> <p>My problem is that I do not know if transposing and zero padding is ok, because it is just a "data format" compatibility problem or if this changes the signal and my simulation is incorrect.</p> <p>I am very new to ultrasound so unfortunately I do not now precisely which waveform I should expect.</p> <p>Thank you! </p>