This invention relates to a non-invasive sensing system for measuring the concentration of a substance within an object, the system including a support means adapted to be placed near to, or against, a surface of the object, a first transmitting antenna mounted upon or within the support means for transmitting electromagnetic radiation signals into the object, and a second receiving antenna mounted upon or within the support means, and adjacent to the first transmitting antenna, for receiving at least a portion of the electromagnetic radiation signals that are reflected back to the same surface of the object covered by the support means, due to the transmitted electromagnetic radiation signals having interacted with the substance within the object being measured.
