Antenna assemblies with antenna elements and reflectors
According to various aspects, exemplary embodiments are provided of antenna assemblies. In one exemplary embodiment, an antenna assembly generally includes at least one antenna element having first and second electrical paths. The antenna assembly may also include at least one reflector element spaced-apart from the antenna element for reflecting electromagnetic waves generally towards the antenna element.
1. An antenna assembly comprising:
at least one antenna element including an upper portion, a lower portion, first and second side portions extending from the lower portion to the upper portion, an intermediate portion extending from the first side portion to the second side portion, the intermediate portion disposed generally between the upper and lower portions, and upper and lower openings respectively defined above and below the intermediate portion;
a first electrical path defined by an outer loop of the antenna element including the upper portion, lower portion, and first and second side portions; and
a second electrical path shorter than the first electrical path, the second electrical path defined by an inner loop of the antenna element including the lower portion, intermediate portion, and corresponding segments of the first and second side portions disposed between the intermediate portion and the lower portion;
wherein:
the upper portion is continuous between the first and second side portions; and/or
the intermediate portion is closer to the upper portion than the lower portion.
2. The antenna assembly of claim 1 , wherein the outer loop defining the first electrical path is generally rectangular, and wherein the inner loop defining the second electrical path is generally rectangular.
3. The antenna assembly of claim 1 , wherein:
the upper portion is continuous between the first and second side portions;
the intermediate portion is closer to the upper portion than the lower portion; and
the first electrical path does not include the intermediate portion.
4. The antenna assembly of claim 1 , further comprising at least one reflector element spaced-apart from the antenna element for reflecting electromagnetic waves generally towards the antenna element, and wherein the reflector element includes a mesh surface and at least one perimeter flange extending outwardly relative to the mesh surface generally towards the antenna element.
5. The antenna assembly of claim 4 , wherein the mesh surface is substantially planar and substantially parallel to the antenna element, and wherein the at least one perimeter flange includes upper and lower perimeter flanges extending outwardly relative to the mesh surface.
6. The antenna assembly of claim 1 , wherein the upper and lower openings of the antenna element are generally rectangular.
7. The antenna assembly of claim 1 , wherein the upper portion, lower portion, and first and second side portions cooperatively define a generally rectangular outer perimeter portion for the antenna element, and wherein the intermediate portion extends from the first side portion to the second side portion generally parallel to the upper and lower portions, such that the antenna element includes generally rectangular upper and lower inner perimeter portions respectively defining the upper and lower openings.
8. The antenna assembly of claim 1 , wherein the intermediate portion is generally perpendicular to the first and second side portions and generally parallel to the upper and lower portions.
9. The antenna assembly of claim 1 , wherein the intermediate portion is configured to improve impedance matching and efficiency of the antenna assembly within a bandwidth ranging from about 170 megahertz to about 216 megahertz.
10. The antenna assembly of claim 1 , wherein:
the lower portion of the antenna element includes spaced-apart end portions defining an open slot extending at least partially between the spaced-apart end portions, whereby the open slot is operable to provide a gap feed for use with a balanced transmission line; and
the intermediate portion is closer to the upper portion than the lower portion.
11. The antenna assembly of claim 1 , further comprising at least one reflector element spaced-apart from the antenna element for reflecting electromagnetic waves generally towards the antenna element, wherein the antenna element has a width of about 600 millimeters and a height of about 400 millimeters, wherein the intermediate portion is spaced above the lower portion by a distance of about 278 millimeters, wherein the reflector element has a width of about 642 millimeters and a height of about 505 millimeters, and wherein the reflector element is spaced apart from the antenna element by a distance of about 200 millimeters.
12. The antenna assembly of claim 1 , further comprising at least one reflector element spaced-apart from the antenna element for reflecting electromagnetic waves generally towards the antenna element, wherein the antenna element is made from aluminum hollow tubing with a ¾ inch by ¾ inch square cross section, and wherein the reflector element is made of vinyl coated steel.
13. The antenna assembly of claim 1 , wherein the antenna assembly is configured for receiving television signals within a frequency range of about 170 megahertz and about 216 megahertz.
14. The antenna assembly of claim 1 , further comprising at least one reflector element spaced-apart from the antenna element for reflecting electromagnetic waves generally towards the antenna element.
15. The antenna assembly of claim 1 , wherein the antenna element is configured for reception of television signals within a bandwidth ranging from about 170 megahertz to about 216 megahertz, and wherein:
the lower portion comprises first and second bottom members having respective first and second end portions;
the upper portion is a top member;
the first and second side portions are respective first and second side members extending upwardly from the respective first and second bottom member to the top member;
the intermediate portion is a tuning bar extending from the first side member to the second side member;
the upper and lower openings are respectively defined above and below the tuning bar;
the first electrical path is defined by the antenna element so as to include the first and second bottom members, the first and second side members, and the top member; and
the second electrical path is shorter than the first electrical path, the second electrical path defined by the antenna element so as to include the first and second bottom members, the tuning bar, and corresponding portions of the first and second side members disposed between the tuning bar and the respective first and second bottom member.
16. The antenna assembly of claim 15 , wherein the first electrical path does not include the tuning bar.
17. The antenna assembly of claim 15 , wherein the upper and lower openings are generally rectangular.
18. The antenna assembly of claim 15 , wherein the top, bottom, and side members cooperatively define a generally rectangular outer perimeter portion for the antenna element, and wherein the tuning bar extends from the first side member to the second side member generally parallel to the top and bottom members, such that the antenna element includes generally rectangular upper and lower inner perimeter portions respectively defining the upper and lower openings.
19. The antenna assembly of claim 18 , wherein the first electrical path is defined by the generally rectangular outer perimeter portion, and wherein the second electrical path is defined by the generally rectangular lower inner perimeter portion.
20. The antenna assembly of claim 15 , wherein the tuning bar is generally perpendicular to the first and second side members and generally parallel to the top and bottom members.
21. The antenna assembly of claim 15 , wherein the tuning bar is configured to improve impedance matching and efficiency within a bandwidth ranging from about 170 megahertz to about 216 megahertz.
22. The antenna assembly of claim 15 , wherein the first and second end portions are spaced-apart thereby defining an open slot extending at least partially between the spaced-apart end portions, whereby the open slot is operable to provide a gap feed for use with a balanced transmission line.
23. The antenna assembly of claim 15 , wherein the antenna element has a width of about 600 millimeters and a height of about 400 millimeters, and wherein the tuning bar is spaced above the first and second bottom members by a distance of about 278 millimeters.
24. The antenna assembly of claim 15 , wherein the antenna element is made from aluminum hollow tubing with a ¾ inch by ¾ inch square cross section.
25. The antenna assembly of claim 15 , further comprising a reflector element, wherein the antenna assembly is operable for receiving television signals within a frequency range of about 170 megahertz and about 216 megahertz.