1. A reflected interferometry system for determining a location of an object in free space, comprising: a plurality of radio frequency transceivers; a location determination module coupled the plurality of radio frequency transceivers; and one or more tags, each of the one or more tags comprising: an antenna; a controller; and a switch, responsive to the controller, and operative to change a radar cross section of each antenna of the one or more tags by selectively altering a load impedance of the each antenna; wherein each of the plurality of radio frequency transceivers is configured to transmit one radio frequency signal and receive a backscattered return signal from each of the one or more tags, each backscattered return signal having a unique identifier corresponding to one of the one or more tags modulated therein due to the controller switching the switch.