A transducer for noninvasively measuring temperature within a body of a subject, comprising: a circuit board having a sensor including a front side and a back side opposite from the front side, and an antenna for receiving at least one native temperature signal from a location of interest within a body of a subject, wherein the sensor is configured to convert the at least one native temperature signal to intermediate temperature signals; a receiving aperture adjacent to the front side of the sensor; an adhesive material adjacent to the front side of the sensor and configured to secure the circuit board to the subject; a dielectric cavity adjacent to the back side of the sensor, the dielectric cavity including an inner extent adjacent to the back side of the sensor and an outer extent opposite from the inner extent; at least one shielding feature positioned adjacent to the inner extent of the dielectric cavity to prevent interfering signals from impinging upon at least the back side of the circuit board; a reference temperature sensor comprising a thermistor configured to sense a temperature at a surface over which the transducer is secured; and a cable connector for connecting to a cable for transmitting a multiplexed signal, the transducer being characterized in that the circuit board carries at least a portion of an electrical circuit including the antenna, a capacitor and the thermistor, the capacitor being positioned in series between the receiving aperture and the thermistor the thermistor being in direct communication with the cable connector, the electrical circuit configured to multiplex intermediate temperature signals from the sensor and reference temperature signals from the reference temperature sensor to form the multiplexed signal. a circuit board having a sensor including a front side and a back side opposite from the front side, and an antenna for receiving at least one native temperature signal from a location of interest within a body of a subject, wherein the sensor is configured to convert the at least one native temperature signal to intermediate temperature signals; a receiving aperture adjacent to the front side of the sensor; an adhesive material adjacent to the front side of the sensor and configured to secure the circuit board to the subject; a dielectric cavity adjacent to the back side of the sensor, the dielectric cavity including an inner extent adjacent to the back side of the sensor and an outer extent opposite from the inner extent; at least one shielding feature positioned adjacent to the inner extent of the dielectric cavity to prevent interfering signals from impinging upon at least the back side of the circuit board; a reference temperature sensor comprising a thermistor configured to sense a temperature at a surface over which the transducer is secured; and a cable connector for connecting to a cable for transmitting a multiplexed signal, the transducer being characterized in that the circuit board carries at least a portion of an electrical circuit including the antenna, a capacitor and the thermistor, the capacitor being positioned in series between the receiving aperture and the thermistor the thermistor being in direct communication with the cable connector, the electrical circuit configured to multiplex intermediate temperature signals from the sensor and reference temperature signals from the reference temperature sensor to form the multiplexed signal.