A time domain kernel to compute a frequency domain solution of the Green's function is successfully implemented on GPU's. If the source receiver distribution illuminates the target from sufficient geometries, individual sensitivity kernels interfere and construct gradients for updates in a FWI scheme. A single frequency full waveform inversion scheme is not applied in a multi-scale velocity refinement as is the standard for the waveform inversion process, but the approach is still able to recover Gaussian anomalies in space.