Microwave tomography (MWT) is a relatively new imaging modality that uses electromagnetic radiation to illuminate an object. Using the scattered field by the object of interest, MWT reconstructs the image of the object. We have been doing research on this topic for a few years and we have successfully developed several computational-imaging algorithms and experimental tomography systems at our imaging lab of the University of Manitoba. In order to increase the accuracy of measurements and calibration procedure, we want to increase the number of probing sites in the system.