Frequency division multiplexing-based techniques for FET-based sensor arrays are provided. In one aspect, a sensor device includes: an array of FET-based sensors, wherein the sensors are grouped into multiple channels, and wherein each of the sensors includes an insulator on a substrate, a local gate embedded in the insulator, a channel material over the local embedded gate, and source and drain electrodes in contact with opposite ends of the channel material, and wherein a surface of the channel material is functionalized to react with at least one target molecule. The sensors in a given channel can be modulated (via the local gate) to enable the signal read out from the channel to be divided in the frequency domain based on the different frequencies used to modulate the sensors.