Image-source model with consideration of air absorption

[Junfeng Li <junfeng@xxxxxxxxxxx>]

Dear list, 

I am now considering to generate room impulse response (RIR) using the well-known image-source method. However, I found that the traditional image-source method only considered the absorption of enclosure surfaces, without the consideration of air absorption. However, the air absorption should be also an important factor which affect the simulated RIR. 

To reformulate the image-source method, the Green function ï exp(jwd/(4*pi*d) ï in the free field should be extended to that with the consideration of air absorption effect. I searched this problem for some days. However, I did not find any reference. 

Could anyone point some references on this issue or the (source code of) improved image-source method that implemented this idea?

Thank you so much in advance.

Best regards,
Junfeng