Abstract: A radio frequency module of a wireless communication device is provided. The radio frequency module is coupled between an antenna and a micro-control unit and includes a radio frequency front-end, a radio frequency integrated circuit, a baseband low-pass filter and a comparator. The radio frequency front-end receives a radio frequency signal through the antenna. The radio frequency integrated circuit receives the radio frequency signal from the radio frequency front-end and converts the radio frequency signal into a baseband signal. The baseband low-pass filter receives the baseband signal from the radio frequency integrated circuit and filters the baseband signal. The comparator compares the filtered baseband signal with a first reference signal and outputs a comparison result signal to the micro-control unit.

Abstract: A device for enhancing electromagnetic susceptibility comprises a first bridge. The first bridge is near to a first trace of a differential pair routing and electrically connects an RF grounding with an analog grounding. The RF grounding and the analog grounding are separated. The differential pair routing transmits signals between an RF circuit and an analog circuit. The first trace of the differential pair routing is closer to an antenna coupled to the RF grounding than a second trace of the differential pair routing. The RF circuit is coupled to the RF grounding, and the analog circuit is coupled to the analog grounding.

Abstract: A wireless security device includes a nonconductive housing, a mother circuit board, a wireless expansion card, and a metal reflector. The mother circuit board and the wireless expansion card are disposed in the nonconductive housing. The mother circuit board includes a processor. The wireless expansion card includes a dielectric substrate, a ground plane, an inverted-F antenna, and an RF (radio frequency) module. The metal reflector is positioned between the mother circuit board and the wireless expansion card, and is close to the inverted-F antenna. The metal reflector is configured to reduce EMI (Electromagnetic Interference) from the mother circuit board so as to maintain performance of the inverted-F antenna.

Abstract: A wireless security device includes a nonconductive housing, a mother circuit board, a wireless expansion card, and a metal reflector. The mother circuit board and the wireless expansion card are disposed in the nonconductive housing. The mother circuit board includes a processor. The wireless expansion card includes a dielectric substrate, a ground plane, an inverted-F antenna, and an RF (radio frequency) module. The metal reflector is positioned between the mother circuit board and the wireless expansion card, and is close to the inverted-F antenna. The metal reflector is configured to reduce EMI (Electromagnetic Interference) from the mother circuit board so as to maintain performance of the inverted-F antenna.

Abstract: A device for enhancing electromagnetic susceptibility comprises a first bridge. The first bridge is near to a first trace of a differential pair routing and electrically connects an RF grounding with an analog grounding. The RF grounding and the analog grounding are separated. The differential pair routing transmits signals between an RF circuit and an analog circuit. The first trace of the differential pair routing is closer to an antenna coupled to the RF grounding than a second trace of the differential pair routing. The RF circuit is coupled to the RF grounding, and the analog circuit is coupled to the analog grounding.