I have been working on simulating the MRI signal and what I have done so far is simulate the actions of the RF pulse and the required localization gradients. So, in the simulation, I am looking at a gradient echo sequence and I have the RF pulse and the slice selection gradient which tips the spin magnetization in the XY plane. This is followed by a rephasing gradient (to take into account the dephasing due to the slice selection gradient).
After this, I have the PE gradient along the Y-direction and the frequency rewinder (to have a symmetrical echo) and the readout gradients along the X-direction.
In the simulator, I am tracking the magnetization vector during the whole process by solving the Bloch equations. Now, the part that I am confused about is how can I convert this to the MRI signal? At the end of the day for each spin, I have its magnetization at every time step. During the readout process, I would like to convert it to the MRI signal and I am not sure how to go about it.