Antenna for facilitating remote reading of utility meters
View Patent ↗An antenna for facilitating remote reading of utility meters is disclosed. The antenna includes a metal rod and a printed circuit board (PCB), both enclosed by an envelope that includes a plastic body and a plastic cap. The plastic body includes a channel for receiving the metal rod. The plastic cap is for covering the plastic body. The PCB includes a dielectric layer located between a first and second metal layers. Secured to the PCB, the metal rod is electrically connected to the second metal layer of the PCB, but not the first metal layer of the PCB.
1. An antenna for facilitating remote reading of utility meters, said antenna comprising:
a printed circuit board (PCB) having a dielectric layer located between a metal layer and a metal trace;
a metal rod secured to said PCB, wherein said metal rod is electrically connected to said metal trace but not electrically connected to said metal layer of said PCB;
a connector includes a signal pin contact and a ground shield contact, wherein said signal pin contact is connected to said metal trace of said PCB, and said ground shield contact is connected to said metal layer of said PCB via a through-hole connector;
an impedance-matching network formed by said metal trace located between said connector and said metal rod, wherein said impedance matching network provides matching impedance between said connector and said metal rod, wherein said impedance-matching network is an impedance-matching metal trace formed by said metal trace to provide quarter-wave impedance matching, wherein an impedance of said impedance-matching metal trace is 22Ω, wherein said metal trace includes a first metal trace section located between said connector and said impedance-matching metal trace, wherein an impedance of said first metal trace section is 50Ω;
a second metal trace section connected between said impedance-matching metal trace and said metal layer of said PCB; and
an envelope for enclosing said metal rod, said PCB and said connector, wherein said envelope includes
a plastic body having a channel to receive said metal rod; and
a plastic cap for covering said plastic body.
2. The antenna of claim 1 , wherein said envelope includes a screw-like structure for attaching said envelope to a lid.
3. The antenna of claim 2 , wherein said screw-like structure includes a plurality of threads.
4. The antenna of claim 2 , wherein said plastic body and said screw-like structure are solid structures made of polypropylene to serve as a dielectric lens for said antenna.
5. The antenna of claim 1 , wherein said metal layer of said PCB serves as an artificial ground plane.
6. The antenna of claim 1 , wherein said antenna further includes a second metal trace section connected between said impedance-matching metal trace and said metal layer of said PCB.
7. The antenna of claim 1 , wherein said metal layer and said metal trace are made of copper.
8. The antenna of claim 1 , wherein said connector is a coaxial connector.
9. The antenna of claim 1 , wherein said metal trace is ¼ wave long.
10. The antenna of claim 3 , wherein said screw-like structure is to be screwed onto a receiving threaded hole located in a lid for covering a water meter pit.