An infrastructure monitoring assembly includes a nozzle cap defining an internal cavity; an antenna positioned at least partially external to the internal cavity; and the antenna covered with a non-metallic material. An infrastructure monitoring assembly includes a nozzle cap defining a first end and a second end, the first end defining a threaded bore configured to mount on a nozzle of a fire hydrant; a cover coupled to the nozzle cap opposite from the first end; an enclosure positioned at least partially between the cover and the first end, the enclosure at least partially defining a cavity; a monitoring device positioned within the cavity; and an antenna positioned between the cover and the first end of the nozzle cap, the antenna connected in electrical communication with the monitoring device, the antenna covered by a non-metallic material.

An infrastructure monitoring assembly includes a nozzle cap defining an internal cavity; an antenna positioned at least partially external to the internal cavity; and the antenna covered with a non-metallic material. An infrastructure monitoring assembly includes a nozzle cap defining a first end and a second end, the first end defining a threaded bore configured to mount on a nozzle of a fire hydrant; a cover coupled to the nozzle cap opposite from the first end; an enclosure positioned at least partially between the cover and the first end, the enclosure at least partially defining a cavity; a monitoring device positioned within the cavity; and an antenna positioned between the cover and the first end of the nozzle cap, the antenna connected in electrical communication with the monitoring device, the antenna covered by a non-metallic material.

An acoustic resonator includes a wafer and a first phononic crystal disposed on the wafer to define an acoustic waveguide so as to propagate an acoustic wave along a propagation direction. The first phononic crystal includes a first two-dimensional (2D) array of metal stripes having a first period on the propagation direction. The apparatus also includes a second phononic crystal and a third phononic crystal disposed on two sides of the first phononic crystal and having a different period from the first period. The second phononic crystal and the wafer define a first reflector to reflect the acoustic wave. The third phononic crystal and the wafer define a second reflector to reflect the acoustic wave.

A terahertz full-duplex co-local oscillator solid-state front-end transmitting circuit is disclosed, which belongs to the technical field of terahertz communication. The overall structure of the solid-state front-end transmitting circuit adopts a new system, wherein the circuit comprises two branches that are parallel and driven by a local oscillator source. A branched waveguide directional coupler is configured to output two driving signals provided by the same local oscillator source respectively to two branch circuits with required powers. Two transmission signals generated from the two branches are combined into one signal for transmission through an orthogonal mode coupled duplexer, so as to fulfill the construction of a full-duplex co-local oscillator solid-state front-end transmission circuit.

A terahertz full-duplex co-local oscillator solid-state front-end transmitting circuit is disclosed, which belongs to the technical field of terahertz communication. The overall structure of the solid-state front-end transmitting circuit adopts a new system, wherein the circuit comprises two branches that are parallel and driven by a local oscillator source. A branched waveguide directional coupler is configured to output two driving signals provided by the same local oscillator source respectively to two branch circuits with required powers. Two transmission signals generated from the two branches are combined into one signal for transmission through an orthogonal mode coupled duplexer, so as to fulfill the construction of a full-duplex co-local oscillator solid-state front-end transmission circuit.

A mounting base (14) is fixed to an antenna (13) or an antenna bracket (15) for supporting the antenna (13). A baseband unit (11) and an RF unit (12) are fixed to the mounting base (14). The baseband unit (11) fixed to the mounting base (14) is disposed to face a back part (132) of the antenna (13) and to form a space between the back part (132) and the first enclosure (111). The RF unit (12) fixed to the mounting base (14) is disposed in the space formed between the back part (132) of the antenna (13) and the baseband unit (11) and is coupled to a waveguide flange (132) of the antenna (13). Thus, for example, in a configuration of a point-to-point wireless apparatus in which an RF unit and a baseband unit are separated, restrictions on installation space of the apparatus can be facilitated.

A mounting base (14) is fixed to an antenna (13) or an antenna bracket (15) for supporting the antenna (13). A baseband unit (11) and an RF unit (12) are fixed to the mounting base (14). The baseband unit (11) fixed to the mounting base (14) is disposed to face a back part (132) of the antenna (13) and to form a space between the back part (132) and the first enclosure (111). The RF unit (12) fixed to the mounting base (14) is disposed in the space formed between the back part (132) of the antenna (13) and the baseband unit (11) and is coupled to a waveguide flange (132) of the antenna (13). Thus, for example, in a configuration of a point-to-point wireless apparatus in which an RF unit and a baseband unit are separated, restrictions on installation space of the apparatus can be facilitated.

The present invention is directed to coated articles demonstrating a transmission of electromagnetic radiation having a frequency of 22 to 81 GHz in the range of 70% to 100%. The articles comprise substrates coated with curable film-forming compositions comprising a first film-forming polymer prepared from at least one hydrophobic monomer, a second film-forming polymer prepared from at least one hydrophobic monomer, and a curing agent. Upon application of the curable film-forming composition to the substrate to form a coating layer, the first film-forming polymer is distributed throughout the coating layer, and the concentration of the second film-forming polymer is greater at the surface of the coating layer than the concentration of the second film-forming polymer within the bulk of the coating layer. The present invention is also drawn to methods of mitigating contaminant build-up on a substrate using the curable film-forming compositions described above.

The present invention is directed to coated articles demonstrating a transmission of electromagnetic radiation having a frequency of 22 to 81 GHz in the range of 70% to 100%. The articles comprise substrates coated with curable film-forming compositions comprising a first film-forming polymer prepared from at least one hydrophobic monomer, a second film-forming polymer prepared from at least one hydrophobic monomer, and a curing agent. Upon application of the curable film-forming composition to the substrate to form a coating layer, the first film-forming polymer is distributed throughout the coating layer, and the concentration of the second film-forming polymer is greater at the surface of the coating layer than the concentration of the second film-forming polymer within the bulk of the coating layer. The present invention is also drawn to methods of mitigating contaminant build-up on a substrate using the curable film-forming compositions described above.

Provided is a waterproof structure to prevent water ingress through an air hole in a casing of a communication device. A waterproof structure for a communication device, the communication device including a casing that houses an electronic substrate and has an air hole, includes a plate member facing the casing and attached to the casing such that the plate member covers the air hole, and a sealing member interposed between the plate member and the casing to prevent ingress of water into the air hole through a gap between the plate member and the casing.