US5943016A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tunable microstrip patch antenna and feed network therefor
Assignee: Engility LLC
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Filing: 1997-04-22
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Granted: 1999-08-24
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Expires: 2017-04-22
Abstract
Abstract A patch antenna is provided with one or more tuning strips spaced therefrom and RF switches to connect or block RF currents therebetween. When a conducting path for RF current is connected between the tuning strips and the patch, the tuning strips increase the effective length of the patch and lower the antenna's resonant frequency, thereby allowing the antenna to be frequency tuned electrically over a relatively broadband of frequencies. If the tuning strips are connected to the patch in other than a symmetrical pattern, the antenna pattern of the antenna can be changed. A feed network couples RF to the antenna and includes two hybrid couplers, one for providing the correct amplitude and phase of excitation at the feed probes, and the second for effectively dissipating reflected power due to antenna impedance mismatch.
Inventors
- 👤 Robert F. Snyder, Jr.
- 👤 James D. Lilly
- 👤 Andrew Humen, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 22:39
CPC Classifications
H; H01; H01Q; H01Q1/00; H01Q1/36; H01Q1/38; H01Q19/00; H01Q19/005; H01Q9/00; H01Q9/04; H01Q9/0407; H01Q9/0421; H01Q9/0442; H01Q9/045; H01Q9/0478
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
208 words
An antenna including: a ground plane that is electrically conductive having a first side surface; a first patch that is electrically conducting having: at least one edge; and a first side surface; a dielectric layer positioned between said first patch and said ground plane, said dielectric layer including: a first side surface in contact with said first side surface of said first patch; and a second side surface in contact with said first side surface of said ground plane; at least one turning strip that is electrically conductive spaced from said at least one edge of said first patch and spaced from said ground plane by said dielectric layer; an RF feed connected to said first patch; switch means to electrically connect and disconnect RF energy between said at least one tuning strip and said first patch; a hybrid coupler network connected to said RF feed, said hybrid coupler network including: a first hybrid coupler connected between said RF feed and an RF power source, said first hybrid coupler having a portion adapted to be connected to a power termination, and a second hybrid coupler connected to said portion of said first hybrid coupler, said second hybrid coupler being adapted to distribute power reflected from said RF feed.
Claim 2
Dependent Claim
208 words
An antenna including: a ground plane that is electrically conductive having a first side surface; a first patch that is electrically conducting having: at least one edge; and a first side surface; a dielectric layer positioned between said first patch and said ground plane, said dielectric layer including: a first side surface in contact with said first side surface of said first patch; and a second side surface in contact with said first side surface of said ground plane; at least one turning strip that is electrically conductive spaced from said at least one edge of said first patch and spaced from said ground plane by said dielectric layer; an RF feed connected to said first patch; switch means to electrically connect and disconnect RF energy between said at least one tuning strip and said first patch; a hybrid coupler network connected to said RF feed, said hybrid coupler network including: a first hybrid coupler connected between said RF feed and an RF power source, said first hybrid coupler having a portion adapted to be connected to a power termination, and a second hybrid coupler connected to said portion of said first hybrid coupler, said second hybrid coupler being adapted to distribute power reflected from said RF feed.
Claim 3
Dependent Claim
55 words
The antenna as defined in claim 1, wherein said RF feed is a pair of feeds that are adapted to feed said RF power to two respective predetermined positions of said first patch, and wherein said hybrid coupler network is adapted to provide a desired phase of said RF power to said pair of feeds.
Claim 4
Dependent Claim
46 words
The antenna as defined in claim 1, wherein said second hybrid coupler includes high power terminations that are adapted to absorb said distributed power reflected from said RF feed, and a low power termination that is adapted to absorb secondary reflections from said high power terminations.
Claim 5
Dependent Claim
46 words
The antenna as defined in claim 2, wherein said second hybrid coupler includes high power terminations that are adapted to absorb said distributed power reflected from said RF feed, and a low power termination that is adapted to absorb secondary reflections from said high power terminations.
Claim 6
Dependent Claim
26 words
The antenna defined in claim 2, wherein said power reflected from said RF feed includes reflected power due to impedance mismatch between said pair of feeds.
Claim 7
Dependent Claim
42 words
The antenna as defined in claim 5, wherein said pair of feeds have a first impedance mismatch when RF energy is not connected between said first patch and said tuning strip and a second impedance mismatch when RF energy is connected therebetween.
Claim 8
Dependent Claim
150 words
An antenna device including: an antenna having: a first patch that is electrically conductive and that is dimensioned such that it has a resonant frequency when RF energy is fed thereto, a tuning strip that, when it is electrically connected to said first patch, changes said resonant frequency thereof, and a switch that electrically connects and disconnects RF energy between said first patch and said tuning strip; an RF feed that feeds RF energy to said first patch; and a hybrid coupler network connected to said RF feed, said hybrid coupler network having: a first hybrid coupler connected between said RF feed and an RF power source, said first hybrid coupler having a portion adapted to be connected to a power termination, and a second hybrid coupler connected to said portion of said first hybrid coupler, said second hybrid coupler being adapted to distribute power reflected from said RF feed.
Claim 9
Dependent Claim
150 words
An antenna device including: an antenna having: a first patch that is electrically conductive and that is dimensioned such that it has a resonant frequency when RF energy is fed thereto, a tuning strip that, when it is electrically connected to said first patch, changes said resonant frequency thereof, and a switch that electrically connects and disconnects RF energy between said first patch and said tuning strip; an RF feed that feeds RF energy to said first patch; and a hybrid coupler network connected to said RF feed, said hybrid coupler network having: a first hybrid coupler connected between said RF feed and an RF power source, said first hybrid coupler having a portion adapted to be connected to a power termination, and a second hybrid coupler connected to said portion of said first hybrid coupler, said second hybrid coupler being adapted to distribute power reflected from said RF feed.
Claim 10
Dependent Claim
55 words
The antenna as defined in claim 7, wherein said RF feed is a pair of feeds that are adapted to feed said RF power to two respective predetermined positions of said first patch, and wherein said hybrid coupler network is adapted to provide a desired phase of said RF power to said pair of feeds.
Claim 11
Dependent Claim
46 words
The antenna as defined in claim 7, wherein said second hybrid coupler includes high power terminations that are adapted to absorb said distributed power reflected from said RF feed, and a low power termination that is adapted to absorb secondary reflections from said high power terminations.
Claim 12
Dependent Claim
46 words
The antenna as defined in claim 8, wherein said second hybrid coupler includes high power terminations that are adapted to absorb said distributed power reflected from said RF feed, and a low power termination that is adapted to absorb secondary reflections from said high power terminations.
Claim 13
Dependent Claim
26 words
The antenna defined in claim 8, wherein said power reflected from said RF feed includes reflected power due to impedance mismatch between said pair of feeds.
Claim 14
Dependent Claim
39 words
The antenna as defined in claim 11, wherein said pair of feeds have a first impedance mismatch when said tuning strip is not connected to said first patch and a second impedance mismatch when said tuning strip is connected.
Claim 15
Dependent Claim
67 words
A hybrid coupler network for matching a power source to a feed including: a first hybrid coupler connected between said feed and said power source, said first hybrid coupler having a portion adapted to be connected to a power termination, and a second hybrid coupler connected to said portion of said first hybrid coupler, said second hybrid coupler being adapted to distribute power reflected from said feed.
Claim 16
Dependent Claim
67 words
A hybrid coupler network for matching a power source to a feed including: a first hybrid coupler connected between said feed and said power source, said first hybrid coupler having a portion adapted to be connected to a power termination, and a second hybrid coupler connected to said portion of said first hybrid coupler, said second hybrid coupler being adapted to distribute power reflected from said feed.
Claim 17
Dependent Claim
35 words
The hybrid coupler network as defined in claim 13, wherein said feed is a pair of feeds, said first hybrid coupler being adapted to provide a desired phase of power to said pair of feeds.
Claim 18
Dependent Claim
47 words
The hybrid coupler network as defined in claim 13, wherein said second hybrid coupler includes high power terminations that are adapted to absorb said distributed power reflected from said feed, and a low power termination that is adapted to absorb secondary reflections from said high power terminations.
Claim 19
Dependent Claim
47 words
The hybrid coupler network as defined in claim 14, wherein said second hybrid coupler includes high power terminations that are adapted to absorb said distributed power reflected from said feed, and a low power termination that is adapted to absorb secondary reflections from said high power terminations.
Claim 20
Dependent Claim
28 words
The hybrid coupler network as defined in claim 14, wherein said power reflected from said feed includes reflected power due to impedance mismatch between said pair of feeds.
Claim 21
Dependent Claim
118 words
The hybrid coupler network as defined in claim 14, wherein said first hybrid coupler includes: a first input port connected to said power source, a second input port comprising said portion adapted to be connected to said power termination, a first output port connected to one of said pair of feeds, and a second output port connected to the other of said pair of feeds, and wherein said second hybrid coupler includes: a first input port connected to said second input port of said first hybrid coupler, a second input port connected to a first termination resistor, a first output port connected to a second termination resistor, and a second output port connected to a third termination resistor.
Claim 22
Dependent Claim
24 words
The antenna as defined in claim 1, wherein said second hybrid coupler distributes said reflected power into two independent paths of approximately equal amplitude.
Claim 23
Dependent Claim
25 words
The antenna device as defined in claim 7, wherein said second hybrid coupler distributes said reflected power into two independent paths of approximately equal amplitude.
Claim 24
Dependent Claim
26 words
The hybrid coupler network as defined in claim 13, wherein said second hybrid coupler distributes said reflected power into two independent paths of approximately equal amplitude.
Claim 25
Dependent Claim
57 words
The antenna as defined in claim 19, wherein said second hybrid coupler includes a first high power termination coupled to one of the two independent paths and a second high power termination coupled to the other of the two independent paths, the first and second high power terminations being; located at different physical locations of the antenna.
Claim 26
Dependent Claim
59 words
The antenna device as defined in claim 20, wherein said second hybrid coupler includes a first high power termination coupled to one of the two independent paths and a second high power termination coupled to the other of the two independent paths, the first and second high power terminations being located at different physical locations of the antenna device.
Claim 27
Dependent Claim
61 words
The hybrid coupler network as defined in claim 21, wherein said second hybrid coupler includes a first high power termination coupled to one of the two independent paths and a second high power termination coupled to the other of the two independent paths, the first and second high power terminations being located at different physical locations of the hybrid coupler network.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2002-08-23 | 2003-02-22 | 2003-08-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-08-23 | 2007-02-22 | 2007-08-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-08-23 | 2011-02-22 | 2011-08-24 | $7700.00 | Window Closed / Lapsed |