# US 9,520,651 B2 · Global navigation satellite system antenna with a hollow core > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,520,651 B2 - Document ID: US9520651B2 - Status: Granted - Kind: B2 - Application number: 14/772,281 - Filed: 2014-01-16 - Published: 2016-01-21 - Granted: 2016-12-13 - Earliest claimed: 2014-01-16 - Assignees: Topcon Positioning Systems, Inc. - Applicants: LLC “Topcon Positioning Systems” - Inventors: Andrey Vitalievich Astakhov; Dmitry Vitalievich Tatarnikov; Pavel Petrovich Shamatulsky - Web page: https://patentgrep.com/patent/US9520651B2 ## CPC - H01Q 13/10: Resonant slot antennas - H01Q 1/48: Earthing means; Earth screens; Counterpoises - H01Q 9/0414: {in a stacked or folded configuration} - H01Q 9/0421: {with a shorting wall or a shorting pin at one end of the element (H01Q9/0414 takes precedence)} - H01Q 9/0428: {radiating a circular polarised wave} - H01Q 21/30: Combinations of separate antenna units operating in different wavebands and connected to a common feeder system - H01Q: ANTENNAS, i.e. RADIO AERIALS (radiators or antennas for microwave heating H05B6/72) ## Abstract Disclosed is a dual-band Global Navigation Satellite System antenna with a hollow core. The antenna includes a conductive cylindrical tube with a longitudinal axis. A ground plane, a low-frequency radiator, and a high-frequency radiator are annuli orthogonal to the longitudinal axis. The inner peripheries of the ground plane and the low-frequency radiator are electrically connected to the outer surface of the cylindrical tube. The outer periphery of the high-frequency radiator is electrically connected to the low-frequency radiator. A vertical low-frequency radiating gap is configured between the ground plane and the outer periphery of the low-frequency radiator. A horizontal high-frequency radiating gap is configured between the inner periphery of the high-frequency radiator and the outer surface of the cylindrical tube. In an embodiment, the inner diameter of the cylindrical tube has a value from about 27 mm to about 102 mm, permitting insertion of a post or pole. ## Claims ### Claim 1 An antenna comprising: a conductive cylindrical tube having: a longitudinal axis; an inner surface having a first inner diameter; and an outer surface having a first outer diameter; a ground plane, wherein: the ground plane comprises a first annulus having: a first circular inner periphery having a second inner diameter; and a first circular outer periphery having a second outer diameter; the ground plane is orthogonal to the longitudinal axis; and the first circular inner periphery is electrically connected to the outer surface; a low-frequency radiator, wherein: the low-frequency radiator comprises a second annulus having: a second circular inner periphery having a third inner diameter; and a second circular outer periphery having a third outer diameter; the low-frequency radiator is orthogonal to the longitudinal axis; the second circular inner periphery is electrically connected to the outer surface; the low-frequency radiator is spaced apart from the ground plane; and a low-frequency radiating gap is configured between the second circular outer periphery and the ground plane; a high-frequency radiator, wherein: the high-frequency radiator comprises a third annulus having: a third circular inner periphery having a fourth inner diameter; and a third circular outer periphery having a fourth outer diameter; the high-frequency radiator is orthogonal to the longitudinal axis; the high-frequency radiator is spaced apart from the low-frequency radiator such that the low-frequency radiator is disposed between the high-frequency radiator and the ground plane; the third circular outer periphery is electrically connected to the low-frequency radiator; and a high-frequency radiating gap is configured between the third circular inner periphery and the outer surface; and a set of high-frequency capacitive elements, wherein: the set of high-frequency capacitive elements is spaced apart from the high-frequency radiator; each high-frequency capacitive element in the set of high-frequency capacitive elements has a first end and a second end; and the first end of each high-frequency capacitive element is electrically connected to the outer surface. ### Claim 2 (depends on 1) The antenna of claim 1, further comprising a set of parasitic elements, wherein: the set of parasitic elements is disposed around the low-frequency radiator and the high-frequency radiator; each parasitic element in the set of parasitic elements has a first end and a second end; and the first end of each parasitic element is electrically connected to the ground plane. ### Claim 3 (depends on 1) The antenna of claim 1, further comprising a set of low-frequency capacitive elements, wherein: the set of low-frequency capacitive elements is disposed between the low-frequency radiator and the ground plane; each low-frequency capacitive element in the set of low-frequency capacitive elements has a first end and a second end; and the first end of each low-frequency capacitive element is electrically connected to the second circular outer periphery. ### Claim 4 (depends on 1) The antenna of claim 1, wherein: the low-frequency radiator is configured to operate with circularly-polarized electromagnetic radiation having a frequency greater than or equal to a first specified frequency and less than or equal to a second specified frequency, wherein the second specified frequency is greater than the first specified frequency; and the high-frequency radiator is configured to operate with circularly-polarized electromagnetic radiation having a frequency greater than or equal to a third specified frequency and less than or equal to a fourth specified frequency, wherein the third specified frequency is greater than the second specified frequency, and the fourth specified frequency is greater than the third specified frequency. ### Claim 5 (depends on 4) The antenna of claim 4, wherein a reference operational wavelength is selected such that the reference operational wavelength is greater than or equal to a first specified wavelength and less than or equal to a second specified wavelength, wherein the first specified wavelength corresponds to the fourth specified frequency and the second specified wavelength corresponds to the first specified frequency. ### Claim 6 (depends on 5) The antenna of claim 5, wherein the first outer diameter has a value from about 0.15 times the reference operational wavelength to about 0.4 times the reference operational wavelength. ### Claim 7 (depends on 4) The antenna of claim 4, wherein: the first specified frequency is about 1165 MHz; the second specified frequency is about 1300 MHz; the third specified frequency is about 1525 MHz; and the fourth specified frequency is about 1605 MHz. ### Claim 8 (depends on 7) The antenna of claim 7, wherein a reference operational wavelength is selected such that the reference operational wavelength is greater than or equal to about 187 mm and less than or equal to about 258 mm. ### Claim 9 (depends on 8) The antenna of claim 8, wherein the first outer diameter has a value from about 28 mm to about 103 mm. ### Claim 10 (depends on 9) The antenna of claim 9, wherein the first inner diameter has a value from about 27 mm to about 102 mm. ### Claim 11 (depends on 1) The antenna of claim 1, further comprising: a set of four low-frequency excitation pins electrically connected to the low-frequency radiator, the set of four low-frequency excitation pins comprising: a first low-frequency excitation pin configured to excite a first low-frequency electromagnetic signal having a first phase; a second low-frequency excitation pin configured to excite a second low-frequency electromagnetic signal having a second phase, wherein a difference between the second phase and the first phase is about 90 degrees; a third low-frequency excitation pin configured to excite a third low-frequency electromagnetic signal having a third phase, wherein a difference between the third phase and the first phase is about 180 degrees; and a fourth low-frequency excitation pin configured to excite a fourth low-frequency electromagnetic signal having a fourth phase, wherein a difference between the second phase and the first phase is about 270 degrees; and a set of four high-frequency excitation pins electrically connected to the high-frequency radiator, the set of four high-frequency excitation pins comprising: a first high-frequency excitation pin configured to excite a first high-frequency electromagnetic signal having a fifth phase; a second high-frequency excitation pin configured to excite a second high-frequency electromagnetic signal having a sixth phase, wherein a difference between the sixth phase and the fifth phase is about 90 degrees; a third high-frequency excitation pin configured to excite a third high-frequency electromagnetic signal having a seventh phase, wherein a difference between the seventh phase and the fifth phase is about 180 degrees; and a fourth high-frequency excitation pin configured to excite a fourth high-frequency electromagnetic signal having an eighth phase, wherein a difference between the eighth phase and the first phase is about 270 degrees. ### Claim 12 (depends on 1) The antenna of claim 1, further comprising: a first printed circuit board having a first top side and a first bottom side, wherein: the ground plane is fabricated on the first top side; and a low-frequency excitation system is fabricated on the first bottom side; and a second printed circuit board having a second top side and a second bottom side, wherein: the high-frequency radiator is fabricated on the second bottom side; the set of high-frequency capacitive elements is fabricated on the second top side; and a high-frequency excitation system is fabricated on the second top side. ### Claim 13 (depends on 12) The antenna of claim 12, further comprising a low-noise amplifier operably coupled to the low-frequency excitation system and the high-frequency excitation system. ### Claim 14 (depends on 13) The antenna of claim 13, wherein the low-noise amplifier is disposed on the first bottom side.