A wafer-level package with a cavity includes a chip, a substrate, and a seal member. By bypassing at least a portion of the MAC PDU parsing of the OFDMOFDMA frame, a particular user terminal need not spend a lot of overhead in the CID filtering process, determining which MAC PDUs are intended to be processed by the MAC of that particular user terminal. An entry code reader transmits entered access codes to the controller. A gain between the output signal and the input signal may be set by a capacitor ratio in said modulator. Power is provided to the electronic sensors through either external or local methods.