Dear Bradley Sir,

I have some conceptual doubt with respect to,

1. What is meant by inverse crime?

2. Just by changing the grid size how can we avoid the inverse crime ?

3. Please suggest reference or textbook to help me understand the matrix A.

The forward model of PAT is represented as

Ax = b, A = system matrix, x = initial pressure and b = measurement.

Based on understanding gained - The system matrix is obtained by solving the governing photoacoustic wave propagation equation (either using Green's function approach or pseudospectral methods or finite difference). In kWave, the command- "kspaceFirstOrder2D" helps us create the A matrix and x to obtain b.

(This becomes our Forward model)

My intention is compute the system matrix and apply the SVE/SVD method to understand the behavior of it.

In the following code , while doing reconstruction (Inverse model/process),

you change the kgrid size in order to avoid the inverse crime but for the rest for the Time reversal example the same kgrid is used (does that mean inverse crime is committed and ignored).

Reference Code:- (i) Attenuation Compensation Using Time Reversal Example

(ii) 2D Time Reversal Reconstruction For A Line Sensor Example

Please do correct me in case I am wrong

Thank you for your time and consideration.

Regards,

Soma