Abstract: A system for low power chemical sensing can include a voltage shift unit which receives a voltage signal from a chemical sensor unit. The voltage signal can be determined by a concentration of an analyte. The voltage shift unit can transform the voltage signal to an input voltage signal, and send the input voltage signal to a plurality of frequency selective surface (FSS) units of an FSS array. The FSS array can communicate a radio frequency (RF) signal in an Institute of Electrical and Electronics Engineers (IEEE) S band with a resonant frequency based on the input voltage to provide the concentration of the analyte.

Abstract: A system for low power chemical sensing can include a voltage shift unit which receives a voltage signal from a chemical sensor unit. The voltage signal can be determined by a concentration of an analyte. The voltage shift unit can transform the voltage signal to an input voltage signal, and send the input voltage signal to a plurality of frequency selective surface (FSS) units of an FSS array. The FSS array can communicate a radio frequency (RF) signal in an Institute of Electrical and Electronics Engineers (IEEE) S band with a resonant frequency based on the input voltage to provide the concentration of the analyte.

Abstract: Systems and techniques for supplying constant electrical power within component tolerances to a resistively changing load in an electrical circuit are described. A method includes receiving an indication of a characteristic voltage associated with a load in an electrical circuit. The method also includes receiving an indication of a characteristic current associated with the load, where the indication of the characteristic current is received as an indication of a second characteristic voltage. The method further includes determining a power consumption associated with the load based upon the indication of the characteristic voltage and the indication of the characteristic current. The method also includes adjusting at least one of a voltage or a current supplied to the load based upon the power consumption associated with the load and a desired constant power consumption for the load.