The present disclosure relates generally to antennas for portable electronic devices, and more specifically to circular polarized antennas, for example, dual-strip transmission line antennas, capable of receiving satellite signals having circular polarized waves and methods therefor.
Satellite-to-earth navigation and communication systems have been operational for many years. These systems often use communication signals having circularly polarized electromagnetic waves. Due to the large distances involved, hand-held wireless communication devices that interface with satellite-to-earth communication and navigation systems require relatively efficient antennas. The most common types of antennas suitable for these systems include Quadrafilar Helix antennas and square micro-strip patch antennas. For portable and especially hand-held applications, the continual challenge is to provide an antenna with good efficiency and sufficient compactness to fit within relatively small form factors.
The various aspects, features and advantages of the disclosure will become more fully apparent to those with ordinary skill in the art, on a careful consideration of the following Detailed Description and the accompanying drawings. The drawings have been simplified for clarity and are not necessarily drawn to scale.
The disclosure concerns antennas suitable for receiving circular polarized signals. Such signals are transmitted by satellites orbiting the earth, among other transmitters. For example, the NAVSTAR Global Positioning System (GPS) satellites currently transmit right-hand circular polarized signals, and some commercial communication satellites transmit left-hand circular polarized signals.
The antenna generally comprises an active element separated from a ground element by a dielectric. The active element is arranged in a partially closed configuration wherein opposite ends thereof are separated by a gap. In one embodiment, the active element has a dimension between the first and second ends thereof corresponding to approximately a single wavelength of the resonant operating frequency of the antenna. In other embodiments, the dimensional length of the active element may correspond to other whole or fractional multiples of the resonant wavelength. Various exemplary embodiments of the antenna and applications thereof are discussed below.
In
In
In one embodiment, the first transmission-line section 114 has a dimension between opposite ends thereof that is approximately one-quarter of the wavelength of the resonant operating frequency of the antenna, and the second transmission-line section 116 has a dimension between opposite ends thereof that is approximately three-quarters of the wavelength of the resonant operating frequency of the antenna. Thus in the exemplary embodiment where the active element has a substantially square configuration, each side has a length that is approximately one-quarter (¼) of the wavelength of the resonant operating frequency of the antenna.
In
The antenna also comprises a feed-point coupled to the active element. The feed-point is generally coupled to the active element between the ends thereof forming the gap. In
The right or left handedness of the circular polarization of the antenna is generally dependent on the geometrical configuration of the active element. In
In some embodiments, the feed-point is reactively coupled to the active element. Generally, the reactance of the coupling may be capacitive and/or inductive. In
In
In one particular application, the antenna is configured to receive a circular polarized signal having a frequency between approximately 2332 MHz and approximately 2345 MHz.
In
In
In an alternative embodiment, the antenna or a portion thereof is integrated with the structure of the display device. In
Generally, the active element loop may be interrupted at one or more locations by reactance elements to cause the resonant frequency or frequencies and impedance(s) to coincide with requirements of the wireless device. The reactive elements may be fixed or they may be under variable control of the host device. In some applications, the circular polarized antenna is capable of being de-activated when other antennas are active. Integrating the antenna or a portion thereof with the display reduces the likelihood that the antenna will not be obstructed by the user, since the user generally handles the device in a manner that provides a clear view of the display with which the antenna is integrated.
While the present disclosure and the best modes thereof have been described in a manner establishing possession by the inventors and enabling those of ordinary skill to make and use the same, it will be understood and appreciated that there are equivalents to the exemplary embodiments disclosed herein and that modifications and variations may be made thereto without departing from the scope and spirit of the inventions, which are to be limited not by the exemplary embodiments but by the appended claims.
The present application is a continuation of U.S. application Ser. No. 11/778,790 filed on 17 Jul. 2007, now U.S. Pat. No. 7,532,164, which is a continuation of U.S. application Ser. No. 11/749,435 filed on 16 May 2007, now abandoned, and claims benefits therefrom under 35 U.S.C. 120.
Number | Name | Date | Kind |
---|---|---|---|
4573053 | Mori et al. | Feb 1986 | A |
4723305 | Phillips et al. | Feb 1988 | A |
5322991 | Hanson | Jun 1994 | A |
5541398 | Hanson | Jul 1996 | A |
6236368 | Johson | May 2001 | B1 |
6307512 | Geeraert | Oct 2001 | B1 |
6308074 | Chandra et al. | Oct 2001 | B1 |
6333716 | Pontoppidan | Dec 2001 | B1 |
6392605 | Anterow | May 2002 | B2 |
6567050 | Briggs | May 2003 | B1 |
6614905 | Kristensen | Sep 2003 | B1 |
6650298 | Abbasi et al. | Nov 2003 | B2 |
6731246 | Parsche et al. | May 2004 | B2 |
6836246 | Kadambi et al. | Dec 2004 | B1 |
6865372 | Mauney et al. | Mar 2005 | B2 |
6904296 | Geeraert et al. | Jun 2005 | B2 |
6919943 | Tsuyuki et al. | Jul 2005 | B2 |
6922574 | Abbasi et al. | Jul 2005 | B2 |
6930644 | Konishi et al. | Aug 2005 | B2 |
20010031645 | Jarrett | Oct 2001 | A1 |
20010050646 | Anterow | Dec 2001 | A1 |
20020032510 | Turnbull et al. | Mar 2002 | A1 |
20020103006 | Doe | Aug 2002 | A1 |
20020111185 | Geeraert et al. | Aug 2002 | A1 |
20020160717 | Persson et al. | Oct 2002 | A1 |
20030003970 | Johnson et al. | Jan 2003 | A1 |
20030083051 | Ntende | May 2003 | A1 |
20030122726 | Abbasi et al. | Jul 2003 | A1 |
20030153281 | Abbasi et al. | Aug 2003 | A1 |
20030222821 | Mikkonen et al. | Dec 2003 | A1 |
20040178958 | Kadambi et al. | Sep 2004 | A1 |
20040196179 | Turnbull | Oct 2004 | A1 |
20050007336 | Albert et al. | Jan 2005 | A1 |
20050020236 | Mauney et al. | Jan 2005 | A1 |
20050024268 | McKinzie, III et al. | Feb 2005 | A1 |
20050032475 | Mauney et al. | Feb 2005 | A1 |
20050068289 | Diefenbaugh et al. | Mar 2005 | A1 |
20050075684 | Phillips et al. | Apr 2005 | A1 |
20050075687 | Phillips et al. | Apr 2005 | A1 |
20050075688 | Toy et al. | Apr 2005 | A1 |
20050075689 | Toy et al. | Apr 2005 | A1 |
20050075692 | Schommer et al. | Apr 2005 | A1 |
20050159107 | Mauney et al. | Jul 2005 | A1 |
20050174290 | Huang | Aug 2005 | A1 |
20050181750 | Pinks | Aug 2005 | A1 |
20080136720 | Parsche et al. | Jun 2008 | A1 |
Number | Date | Country |
---|---|---|
102947 | Jul 2000 | EP |
1018777 | Jul 2000 | EP |
1020948 | Jul 2000 | EP |
1028445 | Aug 2000 | EP |
1122815 | Aug 2001 | EP |
1213838 | Jun 2002 | EP |
1231671 | Aug 2002 | EP |
1271793 | Jan 2003 | EP |
1500991 | Jan 2005 | EP |
1223432 | Mar 2005 | EP |
05275918 | Oct 1993 | JP |
2002-111365 | Apr 2002 | JP |
0131739 | May 2001 | WO |
03069785 | Aug 2003 | WO |
Number | Date | Country | |
---|---|---|---|
20090231229 A1 | Sep 2009 | US |
Number | Date | Country | |
---|---|---|---|
Parent | 11778790 | Jul 2007 | US |
Child | 12433983 | US | |
Parent | 11749435 | May 2007 | US |
Child | 11778790 | US |