http://www.k-wave.org/forum/topic/kramers-kronig-relations-and-powerlawkramerskronig Support for the k-Wave MATLAB toolbox en-US Tue, 12 May 2026 23:31:57 +0000 http://bbpress.org/?v=1.0.2 q http://www.k-wave.org/forum/search.php http://www.k-wave.org/forum/topic/kramers-kronig-relations-and-powerlawkramerskronig#post-5387 Tue, 16 Feb 2016 02:20:26 +0000 Bradley Treeby 5387@http://www.k-wave.org/forum/ <p>Hi Anthony,</p> <p>The absorption value needs to be in Nepers/((rad/s)^y m), rather than Nepers/((MHz)^y m). If you convert, I think this gives c_kk = 1501.2 m/s, which seems to make more sense.</p> <p>Brad. </p> http://www.k-wave.org/forum/topic/kramers-kronig-relations-and-powerlawkramerskronig#post-5373 Mon, 01 Feb 2016 13:54:12 +0000 Anthony 5373@http://www.k-wave.org/forum/ <p>Hi Brad,</p> <p>I have a question about the use of powerLawKramersKronig().</p> <p>I work at a frequency of 3 MHz -&gt; w = 2*pi*3e6 rad/s<br /> I consider a reference frequency of 1 MHz -&gt; w0 = 2*pi*1e6 rad/s<br /> Let's take a reference sound speed of c0 = 1500 m/s<br /> Then, in liver [Pohlhammer 1991] :<br /> a0 = 4.3 Np/m/MHz^y<br /> y = 1.266 </p> <p>Now let's use the function : c_kk = powerLawKramersKronig(w, w0, c0, a0, y)<br /> <code>c_kk = powerLawKramersKronig(2*pi*3e6, 2*pi*1e6, 1500, 4.3, 1.266);</code></p> <p>This gives me c_kk = -0.0047 m/s, which I don't understand.<br /> Is there a problem in the values I use? </p> <p>Best regards,<br /> Anthony </p>