Abstract: An IoT wireless power transfer sensor is provided, which includes a sensor circuit, a group of retrodirective searching antennas, a group of energy harvesting antennas and a communication antenna. The sensor circuit includes a switching unit, an energy converting unit, a power management unit and an energy converting and storage unit. The searching antennas are connected to the switching unit. When the switching unit is on, the searching antennas don't harvest the energy of an external device's scanning signal; they reflect the incident energy to the external device. The energy harvesting antenna is connected to the energy converting unit and receives the incident energy to charge the energy converting and storage unit. When the power storage level of the energy converting and storage unit reaches a first threshold value, the switching unit is consecutively switched between on and off to transmit a device information in back-scattered way to the external device.

Abstract: A smart hub is provided, which includes a control circuit and an antenna array (the functions thereof include transmitting/receiving scanning signals and transmitting wireless power transfer signals). The antenna array is connected to the control circuit and transmits a scanning signal to scan within an effective scanning range thereof. When the antenna array receives the reflected signal of the scanning signal, the control circuit controls the antenna array to keep transmitting a wireless power transfer signal, within a predetermined time interval, in the direction of receiving the reflected signal, and simultaneously receives the device information from a sensor which may exist via the antenna array within the predetermined time interval. The device information is generated by the sensor by backscattering.

Abstract: A smart hub is provided, which includes a control circuit and an antenna array (the functions thereof include transmitting/receiving scanning signals and transmitting wireless power transfer signals). The antenna array is connected to the control circuit and transmits a scanning signal to scan within an effective scanning range thereof. When the antenna array receives the reflected signal of the scanning signal, the control circuit controls the antenna array to keep transmitting a wireless power transfer signal, within a predetermined time interval, in the direction of receiving the reflected signal, and simultaneously receives the device information from a sensor which may exist via the antenna array within the predetermined time interval. The device information is generated by the sensor by backscattering.

Abstract: An IoT wireless power transfer sensor is provided, which includes a sensor circuit, a group of retrodirective searching antennas, a group of energy harvesting antennas and a communication antenna. The sensor circuit includes a switching unit, an energy converting unit, a power management unit and an energy converting and storage unit. The searching antennas are connected to the switching unit. When the switching unit is on, the searching antennas don't harvest the energy of an external device's scanning signal; they reflect the incident energy to the external device. The energy harvesting antenna is connected to the energy converting unit and receives the incident energy to charge the energy converting and storage unit. When the power storage level of the energy converting and storage unit reaches a first threshold value, the switching unit is consecutively switched between on and off to transmit a device information in back-scattered way to the external device.

Abstract: An antenna module includes an antenna and a periodic structure. The periodic structure is disposed on one side of the antenna, and includes a plural first pillars, a plural first bridge members, and a plural second pillars. The plural first pillars are arranged at intervals along a one-dimensional array. The plural first bridge members are arranged at intervals along the one-dimensional array, and are connected to a side of the plural first pillars away from the antenna, wherein the plural first bridge members define a second virtual layer. The plural of second pillars are arranged at intervals in parallel with the first pillars and are connected to a side of the plural first bridge members away from the antenna. Each of the second pillars each of and the first pillars adjacent thereto have an offset from each other in the direction perpendicular to the second virtual layer.