Abstract: This application discloses example radio frequency identification systems and example methods for constructing a relay network, a reader, and a repeater. One example radio frequency identification system includes a reader, a repeater, and a target tag. The reader can be configured to send a first signal to the repeater. The repeater can be configured to send an excitation signal to the target tag based on the first signal. The target tag can be configured to send a target backscatter signal based on excitation of the excitation signal, where the target backscatter signal carries electronic product code information. The reader can be further configured to receive the target backscatter signal and obtain the electronic product code information in the target backscatter signal.

Abstract: The antenna in the embodiments provided includes: a first-layer antenna, a second-layer antenna, a first probe, a second probe, a first connector, and a second connector. An annular microstrip patch is attached to each of main bodies of the first-layer antenna and the second-layer antenna. The annular microstrip patch attached to the first-layer antenna is provided with a first feeding network and a second feeding network therein. The first-layer antenna is connected to the first probe and the second probe by using the first feeding network and the second feeding network respectively. The first-layer antenna is connected to the first connector and the second connector. A position of the first connector corresponds to a position where the first probe is connected to the first-layer antenna. A position of the second connector corresponds to a position where the second probe is connected to the first-layer antenna.

Abstract: This application discloses example radio frequency identification systems and example methods for constructing a relay network, a reader, and a repeater. One example radio frequency identification system includes a reader, a repeater, and a target tag. The reader can be configured to send a first signal to the repeater. The repeater can be configured to send an excitation signal to the target tag based on the first signal. The target tag can be configured to send a target backscatter signal based on excitation of the excitation signal, where the target backscatter signal carries electronic product code information. The reader can be further configured to receive the target backscatter signal and obtain the electronic product code information in the target backscatter signal.

Abstract: The antenna in the embodiments provided includes: a first-layer antenna, a second-layer antenna, a first probe, a second probe, a first connector, and a second connector. An annular microstrip patch is attached to each of main bodies of the first-layer antenna and the second-layer antenna. The annular microstrip patch attached to the first-layer antenna is provided with a first feeding network and a second feeding network therein. The first-layer antenna is connected to the first probe and the second probe by using the first feeding network and the second feeding network respectively. The first-layer antenna is connected to the first connector and the second connector. A position of the first connector corresponds to a position where the first probe is connected to the first-layer antenna. A position of the second connector corresponds to a position where the second probe is connected to the first-layer antenna.

Abstract: The present disclosure discloses a distributed antenna system. The DAS includes a signal source, a first signal generator, a first passive mixer, and a first antenna. The first signal generator is configured to: generate a first local-frequency signal, and send it to the first passive mixer by using a passive DAS line. The first passive mixer is configured to receive the first local-frequency signal, and a downlink radio frequency signal having a second radio frequency band. The first passive mixer is further configured to: perform frequency mixing processing on the received downlink radio frequency signal having the second radio frequency band by using the first local-frequency signal, to form a first downlink radio frequency signal having a first radio frequency band, and then send it to the first antenna. The first antenna is configured to transmit the received first downlink radio frequency signal having the first radio frequency band.

Abstract: The present disclosure relates to antennas, lighting systems, and communications systems. One example antenna includes a radiating element and a feeding unit. The antenna is integrated with a lighting system, where the lighting system includes a protective cover and a light source disposed inside the protective cover. Both the radiating element and the feeding unit of the antenna are integrated with the protective cover of the lighting system. The radiating element is attached to a surface of a cover body of the protective cover that is in a forward direction of the light source. One part of the feeding unit is integrated with the protective cover, and is electrically connected to the radiating element, and the other part of the feeding unit supports an electrical connection to a signal processing device.

Abstract: The present disclosure discloses a distributed antenna system. The DAS includes a signal source, a first signal generator, a first passive mixer, and a first antenna. The first signal generator is configured to: generate a first local-frequency signal, and send it to the first passive mixer by using a passive DAS line. The first passive mixer is configured to receive the first local-frequency signal, and a downlink radio frequency signal having a second radio frequency band. The first passive mixer is further configured to: perform frequency mixing processing on the received downlink radio frequency signal having the second radio frequency band by using the first local-frequency signal, to form a first downlink radio frequency signal having a first radio frequency band, and then send it to the first antenna. The first antenna is configured to transmit the received first downlink radio frequency signal having the first radio frequency band.