A5001622133- Antenna Design and Analysis
- Advanced Antenna and Metasurface Technologies
- Antenna Design and Optimization
- Microwave Engineering and Waveguides
- Structural Analysis and Optimization
- Energy Harvesting in Wireless Networks
- Advanced Materials and Mechanics
- Metamaterials and Metasurfaces Applications
- Advanced Adaptive Filtering Techniques
- Direction-of-Arrival Estimation Techniques
- RFID technology advancements
- Speech and Audio Processing
- Full-Duplex Wireless Communications
- Electromagnetic Compatibility and Measurements
- Advanced MIMO Systems Optimization
- Blind Source Separation Techniques
- Radar Systems and Signal Processing
- Bluetooth and Wireless Communication Technologies
- Radio Frequency Integrated Circuit Design
- Radio Astronomy Observations and Technology
- Wireless Power Transfer Systems
- Sparse and Compressive Sensing Techniques
- Power Line Communications and Noise
- Computational Physics and Python Applications
- Advanced Power Amplifier Design
California Polytechnic State University
2023-2025
Colorado School of Mines
2014-2022
Denver School of Nursing
2021
Association for Women in Science
2021
University of Mississippi
2009-2014
Arizona State University
2013
Tokyo Institute of Technology
2013
Villanova University
2013
Northrop Grumman (United States)
2013
Software (Spain)
2013
Dielectric reflectarray antennas are proposed as a promising low-loss and low-cost solution for high gain terahertz (THz) antennas. Variable height dielectric elements used in the designs, which allow use of low dielectric-constant materials. Polymer-jetting 3-D printing technology is utilized to fabricate antenna, makes it possible achieve rapid prototyping at low-cost. Numerical experimental results presented 3 different prototypes operating 100 GHz, show good performance. Moreover...
A detailed overview of various design methodologies and enabling technologies for beam-scanning reflectarray antennas is presented in this article. Numerous advantages reflectarrays over reflectors phased arrays are delineated, representative antenna designs reviewed. For limited field-of-view systems, utilizing the reflector nature feed-tuning technique can provide a simple solution with good performance. On other hand, applications where wideangle scan coverage required, array aperture...
In this letter, a new design for single-feed dual-band circularly polarized microstrip antennas is presented. A stacked- patch configuration used the antenna, and circular polarization achieved by designing asymmetrical U-slots on patches. The dimensions of are optimized to achieve in both bands. prototype has been designed operate at two frequencies with ratio 1.66. Both experimental theoretical results presented discussed. bandwidth antenna 1.0% 3.5 GHz (WiMax) 3.1% 5.8 (HiperLAN).
In recent years, transmitarray antennas have attracted growing interest with many antenna researchers. Transmitarrays combines both optical and array theory, leading to a low profile design wi
Despite several advantages of planar transmitarray antennas compared to conventional lens antennas, they have a narrow bandwidth. The goal this paper is improve the bandwidth through control transmission phase range and optimization distribution on aperture. To validate proposed approaches, two quad-layer transmitarrays using double square loop elements been designed, fabricated, tested at Ku-band. optimized for both while differ only in ranges. It shown that designed techniques achieve 1-dB...
Reflectarray antennas show momentous promise as a cost-effective high-gain antenna, capable of generating multiple simultaneous beams. A systematic study on various design methods single-feed multi-beam reflectarray is presented in this communication. Two direct for reflectarrays, geometrical method and superposition method, are investigated first. It demonstrated that although both could generate radiation pattern, neither approach provides satisfactory performance, mainly due to high...
This letter investigates a novel bandwidth improvement method, which combines the multilayer approach with subwavelength element technique. A new definition of phase error has been introduced to quantitatively analyze performance reflectarray elements. It is shown that double-layer elements exhibit superior across band, namely an increased range and reduced over frequency. Numerical analysis then performed calculate antennas using these elements, where practical fabrication tolerances at...
A new design methodology is proposed for high-gain beam-scanning reflectarray antennas. Various approaches designing antennas are first reviewed and it shown that limited scan coverage, utilizing the feed displacement technique a convenient approach. To improve single-reflector bifocal aperture phase distribution antenna, further optimized to performance. Four prototypes, each corresponding specific distribution, have been fabricated tested. Ka-band antenna with 60 degrees coverage achieving...
This paper compares two basic methods for analysis of the radiation performance reflectarray antennas. Two different approaches - array theory and aperture field are first described, numerical results then presented various configurations. The advantages limitations each method discussed, compared with other, showing very good agreement. Comparison full-wave simulations showed that these time-efficient can accurately calculate antenna's pattern shape, main-beam direction, beamwidth, sidelobe...
Single-feed reflectarrays with asymmetric multiple beams are studied in this paper. The conventional methods for designing multibeam first reviewed and the limitations of these approaches delineated designs. A generalized design approach based on a global search optimization technique, namely particle swarm optimization, is proposed single-feed reflectarray Practical considerations implementing phase several hundreds elements addressed, designs beam directions gain levels presented....
We present a design methodology for single-feed multibeam transmitarray antennas through case studies of quad-beam designs. Different far-field pattern masks and fitness functions are studied designs, the particle swarm optimization (PSO) technique is implemented aperture phase synthesis. A quad-layer configuration double square loops used elements, prototype fabricated tested. The effects various approximations in unit-cell analysis also investigated detail. Ku-band generates four symmetric...
A bandwidth improvement method in re∞ectarray anten- nas by using closely space elements, i.e., unit-cell sizes smaller than ‚/2, has been investigated both numerically and experimentally this paper. new deflnition of phase error introduced to analyze the broadband mechanism spaced phasing elements. Through full wave EM simulations, it is revealed that elements achieve a over band. Based on these theoretical studies two Ka-band re∞ectarrays were fabricated their performance was measured...
In this paper we report on a broad band reflectarray antenna using sub- wavelength elements based variable size patch element analysis. Two Ka-band reflectarrays single layer sizes as phasing have been developed. One is designed with the conventional lambda/2 spacing and other one lambda/3 spacing. Although both antennas demonstrate good performance, sub-wavelength achieves wider bandwidth.
Reflectarray designs at infrared (IR) frequencies are investigated in this paper. At the short-wavelength region, material loss becomes an important consideration reflectarray designs. Based on measured properties of conductors and dielectrics frequency, paper investigates effects reflection magnitude phase elements. It is revealed that when exceeds a certain limit, element will vary within narrow range instead full 360° range. An equivalent circuit model used to understand phenomenon....
Sparse arrays have grating lobes in the far field pattern due to large spacing of elements residing a rectangular or triangular grid. Random element removes but produces variations density across aperture. In fact, some areas are so dense that overlap. This paper introduces low discrepancy sequence (LDS) for generating locations sparse planar without lobes. nonrandom alternative finds an layout reduces while keeping enough apart practical construction. Our studies consider uniform LDS with...
Beam scanning performance of planar multifocal transmitarray antennas are investigated in this paper. The advantages the proposed structure over conventional designs first delineated, and then a Ku-band antenna with quadrufocal phase distribution is designed using particle swarm optimization technique for 60° scan coverage, which shows good performance. results presented study reveal that can be suitable low-cost choice high-gain beamforming applications.
This paper investigates the feasibility of designing reflectarray antennas on conformal surfaces. A generalized analysis approach is presented that can be applied to compute radiation performance antennas. Using this approach, characteristics singly curved platforms are studied and performances these designs compared with planar designs. It demonstrated a antenna suitable choice for applications requiring high-gain platforms.
Near-field radiative Wireless Power Transfer (WPT) has the advantage of high-power WPT.In this paper, an alltextile WPT receiver is realized for first time, using embroidered coil and a printed tuning capacitor on textile substrate.The proposed demonstrated receiving over 3 W DC power at 6.78 MHz with 23% end-to-end efficiency.A low Specific Absorption Rate (SAR) 0.37 W/kg observed, through full-wave simulation, up to 10 highfrequency input on-body coil, demonstrating its suitability...