Abstract: Multiple sensor signals are used to modulate an equal number of frequency-spaced carrier signals in a directional parametric upconverting amplifier. Basically, the carrier signals are separated in a cascaded or parallel configuration of narrow frequency passbands, which also modulate the carrier signals with low-frequency sensor signals. The modulated carrier signals are multiplexed and output over a single signal path, thereby reducing power dissipation. Preferably implemented in superconducting circuitry, the multiplexed amplifier facilitates multiplexing of as many as hundreds of sensor signals and achieves both amplification and upconverting with minimal dissipation of power.