Apparatuses and systems for determining a temperature of a targeted subject are disclosed. A temperature sensing system may include an antenna for sensing electromagnetic radiation (e.g., microwaves, etc.) emanating from the source. Based on that electromagnetic radiation, the antenna generates a temperature signal. A switch, which is located at or adjacent to an output of the antenna, receives the temperature signal, as well as a reference signal from a termination. The temperature signal and the reference signal are conveyed along a cable to a signal converter. Signal-altering events that affect the temperature signal as it is conveyed also affect the reference signal. Thus, any error caused by a signal-altering event automatically cancels out. The signal converter measures or otherwise processes the temperature signal and, since there is no need to correct for errors in the temperature signal, the reference signal, and accurately calculates the temperature of the source.
