A passive wireless sensor having a plurality of dielectric layers, an antenna, a diaphragm, and a feeding element is provided. Further, the antenna is disposed in at least a portion of a cavity formed by one or more dielectric layers of the plurality of dielectric layers. Moreover, the diaphragm is disposed on the cavity. Additionally, the feeding element is disposed in at least a portion of the plurality of dielectric layers. Also, the feeding element is operatively coupled to the antenna.