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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

3D Near Isotropic Antenna in Package for IoT Applications

Su, Zhen 11 1900 (has links)
Internet of Things (IoT) is an emerging paradigm about building a massive internet to link billions of non-living things to make smart decisions for humans and improve their quality of life. For many of IoT devices, such as wireless sensor nodes dispersed in the environment, there is not much control over their placements or orientations. Thus, there is a need to develop orientation insensitive antennas that ensure reliable data transmission irrespective of devices’ positions or orientations. As billions of such IoT devices required in the future, a low-cost fabrication process suitable for mass manufacturing must be adapted. Antenna in package (AiP) concept is beneficial that the package is utilized to realize the antennas, not only saving space but also reducing the overall cost. For orientation insensitivity, antennas must be near isotropic and even have to maintain their radiation pattern for multi-bands or wide bandwidths in most applications. However, there is a dearth in the literature about design methodologies for near isotropic antennas, particularly for multi-bands near isotropic AiP designs. In addition, a near isotropic behavior is also important for polarization, particularly for CP antennas. To have simultaneous isotropy in radiation pattern and circular polarization is challenging. In the nut shell, this thesis presents theoretical models and derives conditions for wire AiP design for different specifications, single-band and dual-band near isotropic antennas, null free near isotropic antenna with wide CP coverage, and a full CP antenna with decent near isotropy (with very narrow null beam). The single-band AiP has only 5.05 dB gain variation at WiFi/BLE band and the dual-band AiP has a decent near isotropic radiation property and covers both GSM900 and GSM1800 bands. The theoretical model for null-free near isotropic antenna with wide CP coverage is presented with particle swarm optimization (PSO). The full CP antenna has a measured CP coverage of 70% with a small null in the radiation pattern. The results are promising and indicate that the conditions and methods proposed are useful for the future near isotropic AiP design. Also, this work provides designers flexibility to adjust the AiP design according to their own applications.
2

Modeling & Development of Wirelessly Coupled Loops for Chip-to-Antenna Communications

Johnstone, Jonathan 10 September 2013 (has links)
This thesis examines the use of two coupled loops as an alternative method of connection for high frequency signals between passive elements on microwave laminates and integrated circuits; replacing traditional interconnect methods such as wire bonds and solder bumps which require costly back end of line processing. The loops harness both electric and magnetic fields in order to create the interconnection, and can be placed around the perimeter of the IC; here they do not interfere with placement of the existing electronics on the chip, or occupy space which may be required for large components such as spiral inductors. A parametric model for these coupled loops was developed in this thesis. This model allows for rapid initial dimension choice when provided a variety of different parameters such as the IC process geometry, and loop stack geometry. Once initial dimensions are obtained from the model, full-wave simulation can be used to finalize the design and examine effects of process design rules such as metal density requirements. Following model development a prototype system, consisting of a two metallic loops (one located on a low-loss microwave laminate, the other on a 0.13 u m CMOS IC), was fabricated. These loops were then stacked in order to couple the signal from a planar antenna array (printed on the laminate) onto the IC. This antenna-to-chip system was simulated and measured to have center frequencies of 25 GHz and 23 GHz respectively, with a peak gain greater than 5 dBi at the beams broadside (8 dBi in simulation). These results agree quite well, with discrepancies arising primarily from the presence of adhesive between the loops. This adhesive wicked underneath the IC during assembly, which was not accounted for during simulation, but can easily be done so. The radiation pattern from the antenna was measured to have a HPBW of 16 degrees in the elevation plane and 100 degrees in the azimuth plane. These correspond nicely with simulated results and produce a suitable system for automotive radar application; where harsh environments present difficulties to current interconnects such as wire bonds. / Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2013-09-09 21:55:06.971
3

Design and development of organically packaged components and modules for microwave and Mm-wave applications

Khan, Wasif Tanveer 12 January 2015 (has links)
Because of the tremendous amount of media streaming, video calling and high definition TV and gaming, the biggest challenge for the wireless industry is the increasing demand of high data rates. Utilization of mm-wave frequencies is an attractive option to meet this high demand. Recent advances in low cost semiconductor technologies allow realization of low-cost on-chip RF front-ends in the high millimeter wave (mm-wave) frequencies, making it possible to realize compact systems for these application areas. Although integrated circuits (ICs) are one of the main building blocks of a mm-wave system, in order to realize a fully functional wireless system, cost-effective antenna design and packaging are two important pre-conditions. Researchers have investigated and reported low-cost electronics packaging up to 100 GHz to a great extent on ceramic substrates, but mm-wave packaging above 100 GHz is relatively less explored, particularly on organic substrates. This Ph.D. dissertation demonstrates the design and development of microwave and mm-wave on-chip and on-package antennas and organically packaged components and modules ranging from 20 GHz to 170 GHz. The focus of this research was to design and develop mm-wave components and modules on LCP, to investigate the viability of this organic substrate and development of fabrication techniques in the K- (18-26.5 GHz), V- (50 to 70 GHz), W- (75 to 110 GHz), and D- (110 to 170 GHz) bands. Additionally, a demonstration of a micro-machined on-chip antenna has also been presented. This dissertation is divided in three parts: (1) characterization of liquid crystal polymer from 110 to 170 GHz. (2) development of highly radiation efficient on-chip and AiP antennas, and (3) development of mm-wave modules with the integration of antennas.

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