US-12620710-B2 - Electronic device with isoflux antenna and related methods

Abstract

An electronic device includes an RF device, and an antenna. The antenna includes an elongate support, and helically wound conductive strips carried by the elongate support and with adjacent conductive strips having an angular spacing. The electronic device includes a feed structure coupling the RF device to the helically wound conductive strips.

Inventors

• Francis E. PARSCHE
• Edward G. Palmer
• OLIVIA STANNARD

Assignees

• EAGLE TECHNOLOGY, LLC

Dates

Publication Date

20260505

Application Date

20240129

Claims (20)

1. 1 . An electronic device comprising: a radio frequency (RF) device; an antenna comprising an elongate support, and a plurality of helically wound conductive strips having inside edges carried by the elongate support and with adjacent conductive strips having an angular spacing therebetween; and an inductive feed structure coupling the RF device to the plurality of helically wound conductive strips, the inductive feed structure comprising a respective insulated conductor coupled to an outside edge of each helically wound conductive strip.
2. 2 . The electronic device of claim 1 wherein the plurality of helically wound conductive strips comprises four strips.
3. 3 . The electronic device of claim 2 wherein the angular spacing between adjacent strips is ninety degrees.
4. 4 . The electronic device of claim 1 wherein the elongate support comprises a dielectric rod.
5. 5 . The electronic device of claim 1 comprising a dielectric tube surrounding the plurality of helically wound conductive strips.
6. 6 . The electronic device of claim 1 wherein the antenna comprises a ground plane adjacent proximal ends of the plurality of helically wound conductive strips.
7. 7 . The electronic device of claim 1 wherein respective distal ends of the plurality of helically wound conductive strips are electrically coupled together.
8. 8 . The electronic device of claim 1 wherein each of the plurality of helically wound conductive strips has a constant helical pitch along the elongate support.
9. 9 . The electronic device of claim 1 wherein the antenna has an isoflux antenna gain pattern; and wherein the antenna has an operating frequency in a range of 1100-1700 MHZ; and wherein the antenna has a diameter between 0.2 and 0.6 wavelengths of the operating frequency.
10. 10 . An isoflux antenna device for a radio frequency (RF) device, the isoflux antenna device comprising: an elongate support; a plurality of helically wound conductive strips having inside edges carried by the elongate support and with adjacent conductive strips having an angular spacing therebetween; and an inductive feed structure for coupling the RF device to the plurality of helically wound conductive strips, the inductive feed structure comprising a respective insulated conductor coupled to an outside edge of each helically wound conductive strip.
11. 11 . The isoflux antenna device of claim 10 wherein the plurality of helically wound conductive strips comprises four strips.
12. 12 . The isoflux antenna device of claim 11 wherein the angular spacing between adjacent strips is ninety degrees.
13. 13 . The isoflux antenna device of claim 10 wherein the elongate support comprises a dielectric rod.
14. 14 . The isoflux antenna device of claim 10 comprising a dielectric tube surrounding the plurality of helically wound conductive strips.
15. 15 . The isoflux antenna device of claim 10 further comprising a ground plane adjacent proximal ends of the plurality of helically wound conductive strips.
16. 16 . The isoflux antenna device of claim 10 wherein respective distal ends of the plurality of helically wound conductive strips are electrically coupled together.
17. 17 . A method for making an antenna for an electronic device, the method comprising: forming the antenna comprising an elongate support, and a plurality of helically wound conductive strips having inside edges carried by the elongate support and with adjacent conductive strips having an angular spacing therebetween; and coupling an inductive feed structure to the plurality of helically wound conductive strips, the inductive feed structure comprising a respective insulated conductor coupled to an outside edge of each helically wound conductive strip.
18. 18 . The method of claim 17 wherein the plurality of helically wound conductive strips comprises four strips.
19. 19 . The method of claim 18 wherein the angular spacing between adjacent strips is ninety degrees.
20. 20 . The method of claim 17 wherein the elongate support comprises a dielectric rod.

Description

TECHNICAL FIELD The present disclosure relates to the field of communications, and, more particularly, to a wireless communications device and related methods. BACKGROUND Although the field of antennas is approximately 130 years old, antenna types and their designs may remain artisan in nature. Radiation pattern requirements, in and of themselves, may not suggest all possible antenna shapes that are useful. For example, Fourier Transform techniques may refer to a radiation pattern shape and to a planar antenna aperture current distribution. Nonetheless, the Fourier Transform may not easily define an end fire antenna. During a golden age for antenna design, many of the Euclidian geometries were implemented in metal and used as antennas with useful results. Examples may comprise: the line-based wire dipole, the circular loop, the conical horn, and the parabolic reflector antenna, etc. The Euclidian shapes may offer optimizations of the shortest distance between two points for the line dipole. Also, these shapes may offer maximum radiation resistance for length, most area enclosed for least circumference for circular loops and circular patches, and maximum directivity for aperture area. Elongate antennas may be desirable for Earth satellites as planar broadside firing antennas may not fit within a limited satellite size and area. An elongate antenna of high directivity and gain is provided by a cascade of multiple dipoles known as the Yagi-Uda Antenna. (“Beam Transmission Of Short Waves”, Proceedings of the Institute Of Radio Engineers, 1928, Volume 16, Issue 6, pages 715-740). This reference referred to the many directors as a “wave canal”. A Yagi-Uda antenna may be narrow in bandwidth, which limits its application, and the beam may be asymmetric. In an existing approach, an antenna providing circular polarization is an axial mode wire helix antenna. An example is disclosed in “Helical Beam Antennas For Wide-Band Applications”, John D. Kraus, Proceedings Of The Institute Of Radio Engineers, 36, pp 1236-1242 October 1948. An improvement to the wire axial mode helix is found in U.S. Pat. No. 5,892,480 to Killen, assigned to the present application's assignee. This approach for a directional antenna comprises a helix-shaped antenna. Although this antenna is directional, the gain and bandwidth performance may be less than desirable. For low Earth orbit (LEO) satellites, it may be helpful to have a “isoflux” radiation pattern. In particular, this special shape antenna radiation pattern may provide a constant signal strength on the Earth surface from LEO satellites. Since the LEO satellite is moving relative to the surface of the Earth, the signal strength may vary without the special isoflux radiation pattern. In particular, a lower gain is needed straight down at nadir, and a higher gain is needed towards the horizon. SUMMARY Generally, an electronic device comprises a radio frequency (RF) device, and an antenna. The antenna comprises an elongate support, and a plurality of helically wound conductive strips carried by the elongate support and with adjacent conductive strips having an angular spacing therebetween. The electronic device comprises a feed structure coupling the RF device to the plurality of helically wound conductive strips. In some embodiments, the feed structure may comprise a plurality of electrically conductive feeds coupling the RF device to respective proximal ends of the plurality of helically wound conductive strips. Also, the plurality of helically wound conductive strips may comprise four strips. The angular spacing between adjacent strips may comprise ninety degrees, for example. Also, the elongate support may comprise a dielectric rod, and the plurality of helically wound conductive strips may extend outwardly from the dielectric rod. In other embodiments, the elongate support may comprise a dielectric tube surrounding the plurality of helically wound conductive strips. The antenna may comprise a ground plane adjacent the feed structure. Respective distal ends of the plurality of helically wound conductive strips may be electrically coupled together. Each of the plurality of helically wound conductive strips may have a constant helical pitch along the elongate support. Each of the plurality of helically wound conductive strips may include a corrugated helically wound conductive strip. The antenna may have an isoflux antenna gain pattern. For example, the antenna may have an operating frequency in a range of 1100-1700 MHz, and the antenna may have a diameter between 0.2 and 0.6 wavelengths of the operating frequency. Another aspect is directed to an isoflux antenna device for an RF device. The isoflux antenna device comprises an elongate support, a plurality of helically wound conductive strips carried by the elongate support and with adjacent conductive strips having an angular spacing therebetween, and a plurality of electrically conductive feeds coupling the RF device to respective prox