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Wideband Tunable PIFA Antenna with Loaded Slot Structure for Mobile Handset and LTE ApplicationsElfergani, Issa T., Hussaini, Abubakar S., Rodriguez, Jonathan, See, Chan H., Abd-Alhameed, Raed 04 1900 (has links)
Yes / A compact planar inverted F antenna (PIFA) with a tuneable frequency response is presented. Tuning of the resonant frequency is realized by loading a varactor on an embedded slot of the proposed antenna structure without further optimizing other antenna geometry parameters. The antenna exhibits a wide frequency range from 1570 to 2600 MHz with a good impedance matching (S11 ≤ -10dB) covering the GPS, PCS, DCS, UMTS, WLAN and LTE systems. To validate the theoretical model and design concept, the antenna prototype was fabricated and measured. The compact size of the antenna is 15mm × 8mm × 3mm, which makes this antenna a good candidate for mobile handset and wireless communication applications.
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Development of Integrated "Chip-Scale" Active Antennas for Wireless ApplicationsZhao, Jun 27 August 2002 (has links)
With the rapid expansion of wireless communication services, ultra-miniature, low cost RF microsystems operating at higher carrier frequencies (e.g. 5-6 GHz) are in demand for various applications. Such applications include networked wireless sensor nodes and wireless local area data networks (WLANs). Integrated microstrip antennas coupled directly to the RF electronics, offer potential advantages of low cost, reduced parasitics, simplified assembly and design flexibility compared to systems based on discrete antennas. However, the size of such antennas is governed by physical laws, and cannot be arbitrarily reduced. The critical patch antenna dimension at resonance needs to be ~ λ<sub>g</sub>/2 (where λ<sub>g</sub> is the guided wavelength given by λ<sub>g</sub>=λ₀/√(𝜖<sub>r</sub>) . Several methods are available to reduce the physical size of the antenna to enable on-chip integration. A high dielectric constant substrate reduces the guided wavelength. Grounding one edge of the microstrip patch enables the resonant antenna length to be further reduced to ~ λ<sub>g</sub>/4. However, these techniques result in degraded antenna efficiency and bandwidth. Nonetheless, such antennas still have potential for use in low power/short range applications.
In this work, "electrically small" (small with respect to λ₀) square-shaped microstrip patch antennas, grounded on one edge by shorting posts, have been investigated. The antenna input impedance depends on the feed position; by adjusting the feed point, the antenna can be tuned to match a 50 Ω or other system impedance. The antennas were designed on a GaAs substrate, with a high dielectric constant of 12.9. The size of the patch antenna is further reduced by utilizing shorted through substrate vias along one edge. The size of the antenna is about 4.2mm × 4.2mm, which is ~1/13 of λ₀ at ~5.6GHz. The antennas are practical for integration on chip. Due to the size reduction, the simulated peak gain of the antenna is only −10.2 dB (~3.2% radiation efficiency). However, this may be acceptable for short-range wireless communications and distributed sensor network applications.
Based on the above approach, integrated GaAs "chip-scale" antennas with matching power amplifiers have been designed and fabricated. Class A tuned MESFET power amplifiers (PAs) were designed with outputs directly matched to the antenna feed point. The antenna is fabricated on the backside of the chip through backside patterning; the PA feeds the antenna through a backside via. The structure is then mounted such that the antenna faces up, and is compatible with flip-chip technology. The measurement of a 50 Ω passive (no PA) antenna indicates a gain of -12.7dB on boresight at 5.64 GHz, consistent with the antenna size reduction. The measurement of one active antenna (50 Ω system) shows a gain of -4.3dB on boresight at 5.80 GHz. The other version of active antenna (22.5 Ω system) shows a gain of −2.9 dBi on boresight at 5.725 GHz. The active circuitry (PA) contributes an average of ~9 dB gain in the active antenna, reasonable close to the designed PA gain of 12.7dB. The feasibility of direct integration of a PA with an on-chip antenna in a commercial GaAs process at RF frequencies was successfully demonstrated. / Master of Science
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Design of controlled RF switch for beam steering antenna arrayAbusitta, M.M., Zhou, Dawei, Abd-Alhameed, Raed, Excell, Peter S. January 2008 (has links)
Yes / A printed dipole antenna integrated with a duplex RF switch used for mobile base
station antenna beam steering is presented. A coplanar waveguide to coplanar strip transition was adopted to feed the printed dipole. A novel RF switch circuit, used to control the RF signal fed to the dipole antenna and placed directly before the dipole, was proposed. Simulated and
measured data for the CWP-to-CPS balun as well as the measured performance of the RF switch are shown. It has demonstrated the switch capability to control the beam in the design of beam steering antenna array for mobile base station applications.
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LOW-COST RAPID-RESPONSE EMBEDDED ANTENNA DESIGN FOR US ARMY 60MM MORTARSKatulka, G., Hall, R., Peregino, P., Muller, P., Hundley, N., McGee, R. 10 1900 (has links)
ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / The Defense Advanced Research Projects Agency (DARPA) and the US Army are engaged in a
high-risk/high-payoff project for the development of precision-guided 60mm mortars for the
benefit of the optically designated attack munition (ODAM). This paper describes the antenna
design and performance characteristics required for a telemetry-based onboard diagnostic
system. Efforts executed at the U.S. Army Research Laboratory, Aberdeen Proving Ground, MD
met our primary objective to demonstrate rapid response low-cost capability for body-mounted
antennas compatible with commercially-available telemetry products. This presentation reviews
the theoretical design and antenna radiation pattern characteristics, tuning process, and returned
in-flight signal strength along the trajectory. Experimental results compared favorably with
theoretical link analyses. Lessons learned, ongoing applications, and future improvements are
also presented.
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3D Printed Antennas for Wireless CommunicationJohnson, Brent, Madrid, Colin, Yiin, Kevin, Wang, Hanwen, Li, Chengxi, Tan, Xizhi 10 1900 (has links)
ITC/USA 2015 Conference Proceedings / The Fifty-First Annual International Telemetering Conference and Technical Exhibition / October 26-29, 2015 / Bally's Hotel & Convention Center, Las Vegas, NV / This paper describes the details of design and critical analysis of the process of 3D printing antennas for wireless communications applications. The subjective testing methods utilized were chosen specifically based on project scope and researcher capability. Our results indicate that more work is necessary in this field but that the basic idea is feasible.
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Analysis of millimetre wave antennasLindley, Edward Andrew January 1990 (has links)
No description available.
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Characterisation and investigation of multiple-input multiple-output wireless communication channelsMcNamara, Darren Phillip January 2003 (has links)
No description available.
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Angle of arrival estimation using artificial neural networksWells, Patricia D. January 1996 (has links)
No description available.
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Millimetre-wave microstrip antennas and hybrid typesHall, C. M. January 1987 (has links)
No description available.
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High Data Rate Modulation Issues in Millimeter-Wave MetamaterialsFranson, Steven January 2007 (has links)
This dissertation examines the use of metamaterial structures in millimeter-wave communication systems. Metamaterials, which are composite structures that have electromagnetic properties not found in nature, have been an area of explosive growth in academic research, including applications such as electrically small antennas, sub-wavelength imaging, and negative phase velocity transmission lines. In this dissertation, several potential applications of metamaterials are investigated, including new ideas related to negative forces. The design of highly directive antennas and their use in high data rate communication systems are emphasized. At millimeter-wave frequencies, specifically in a frequency band around 60 GHz, there is an enormous amount of available unlicensed worldwide spectrum available for data transmission. These systems may benefit from the knowledge of metamaterials and their integration with antenna systems. Although there are many challenges with working at such high frequencies and the metamaterials themselves are inherently dispersive and lossy, it will be demonstrated that useful structures can be designed and fabricated at these frequencies. Metamaterial-based artificial magnetic conductors were designed and it has been shown that they can handle 'gigabit per second' data rates. Moreover, superstrate structures were also designed to achieve near zero-index of refraction properties and, as a result, highly directive 60 GHz antenna systems. These metamaterial superstrate-based patch antennas were built and tested successfully with actual 'gigabit per second' data rates. Design and practical fabrication challenges associated with these millimeter-wave applications were addressed and will be reviewed.
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