Metamaterial-Inspired Efficient Electrically Small Antenna

Abstract—Planar two-dimensional (2D) and volumetric threedimensional (3D) metamaterial-inspired efficient electrically-small antennas that are easy to design; are easy and inexpensive to build; and are easy to test; are reported, i.e., the EZ antenna systems. The proposed 2D and 3D electrical- and magnetic-based EZ antennas are shown to be naturally matched to a 50 source, i.e., without the introduction of a matching network. It is demonstrated numerically that these EZ antennas have high radiation efficiencies with very good impedance matching between the source and the antenna and, hence, that they have high overall efficiencies. The reported 2D and 3D EZ antenna designs are linearly scalable to a wide range of frequencies and yet maintain their easy-to-build characteristics. Several versions of the 2D EZ antennas were fabricated and tested. The measurement results confirm the performance predictions. The EZ antennas systems may provide attractive alternatives to existing electrically-small antennas. Index Terms—Antenna efficiency, antennas, electrically small antenna (ESA), metamaterials. I

Statistical Power Supply Dynamic Noise Prediction in Hierarchical Power Grid and Package Networks

One of the most crucial high performance systems-on-chip design challenge is to front their power supply noise sufferance due to high frequencies, huge number of functional blocks and technology scaling down. Marking a difference from traditional post physical-design static voltage drop analysis, /a priori dynamic voltage drop/evaluation is the focus of this work. It takes into account transient currents and on-chip and package /RLC/ parasitics while exploring the power grid design solution space: Design countermeasures can be thus early defined and long post physical-design verification cycles can be shortened. As shown by an extensive set of results, a carefully extracted and modular grid library assures realistic evaluation of parasitics impact on noise and facilitates the power network construction; furthermore statistical analysis guarantees a correct current envelope evaluation and Spice simulations endorse reliable result

Analysis And Design Of Low Profile Multiband Multifunctional Antenna Arrays

Light-weight phased array antennas for aerospace and mobile applications require utilizing the same antenna aperture to provide multiple functions with dissimilar radiation pattern specifications (e.g., multiband operation for communications and tracking). Multi-functional antennas provide advantages over aggregate antenna clusters by reducing space requirements, and can aid in the optimal placement of all required apertures to provide adequate isolation between channels. Furthermore, the combination of antenna apertures into a comgeometry mitigates co-site installation issues by addressing interference within the integrated radiator design itself as opposed to the extensive analysis which is required to configure multiple radiators in close proximity. The combination of multiple radiators into a single aperture can only be achieved with the proper selection of antenna topology and accompanying feed network design. This research proposes a new technique for the design of multiband arrays in which a comaperture is used. Highlighted by this method is the integration of a tri-band array comprised of an x-band (12 ghz) microstrip patch array on a superstrate above printed dual-band (1 and 2 ghz) slot loop antenna arrays in an octave-spaced lattice. The selection of a ground backing reflector is considered for improved gain and system packaging, but restricts the utility of the design principally due to the î›/4 depth of the ground plane. Therefore, a novel multiband high impedance surfaces (his) is proposed to load the slot apertures for reduced height. The novel techniques proposed here will enable the design of a low profile and conformal single aperture supporting multi-band and multi-functional operations

Design considerations for a monolithic, GaAs, dual-mode, QPSK/QASK, high-throughput rate transceiver

A monolithic, GaAs, dual mode, quadrature amplitude shift keying and quadrature phase shift keying transceiver with one and two billion bits per second data rate is being considered to achieve a low power, small and ultra high speed communication system for satellite as well as terrestrial purposes. Recent GaAs integrated circuit achievements are surveyed and their constituent device types are evaluated. Design considerations, on an elemental level, of the entire modem are further included for monolithic realization with practical fabrication techniques. Numerous device types, with practical monolithic compatability, are used in the design of functional blocks with sufficient performances for realization of the transceiver

Paper-based Screen-printed Passive Electronic Components

This thesis investigates paper-based electronics in terms of various substrates, fabrication methods and example devices, including touch sensors and microwave resonators. The term ‘paper’ is very broad and covers a wide range of substrates. A decision matrix has been created to determine the optimum paper for an application, based on a range of properties. Thermal evaporation and screen printing are compared for their use as fabrication methods for paper-based electronics and a second decision matrix has been compiled. Based on these decision matrices, screen printing onto a thicker matt paper was determined to be optimal. The printing process was further optimised to achieve the best results from the in-house process. Using this well-developed screen-printing method, passive components (including inductors and interdigitated capacitive touch sensors) were fabricated and found to be comparable with state-of-the- art results reported in the literature. Measurements from the touch pads were compared to modelling, with little variation between the two, and were confirmed to work under a wide range of conditions, showing that they are compatible with any user. The microwave characteristics, up to 3GHz, of both the chosen substrate and silver-flake ink were investigated through production of screen-printed transmission lines. These characteristics were then used to create microwave resonators. The frequency range is important for applications as the industrial, scientific and medical radio band (ISM band) lies between 2.45 and 2.55 GHz which includes Wi-Fi and Bluetooth. Initially, stub resonators were considered to determine the cause of differences between theoretical and measured results. Then spiral defected ground structures were made, with multiple resonances, and sensitivity to touch and humidity demonstrated. As paper is hygroscopic, the effect of humidity on paper-based electronics is of key importance. This has been considered for all the devices fabricated in this work and it has been determined that the change in permittivity of the substrate, as a result of absorbed water within paper, is the most dominant factor

Metamaterial antennas for cognitive radio applications

Cognitive radio is one of the most promising techniques to efficiently utilize the radio frequency (RF) spectrum. As the Digital Video Broadcasting-Handheld (DVB-H) band is targeted (470-862 MHz), the size of the antenna becomes challenging. Metamaterial concept is used as a miniaturization technique. Two antennas are designed, fabricated and measured. The first one achieved multiband operation by loading it with a metamaterial unit cell. These bands are controlled by engineering the dispersion relation of the unit cell. The second one, which is a 2-lumped elements loaded antenna, achieved wideband operation through the entire DVB-H band with a planar size of 5×2 cm^2. A model is proposed to explain, through simple numerical simulations and an optimization algorithm, the behavior of these component loaded antennas (which are equivalent to metamaterial inspired electrically small antennas)

On-Chip Power Supply Noise: Scaling, Suppression and Detection

Design metrics such as area, timing and power are generally considered as the primary criteria in the design of modern day circuits, however, the minimization of power supply noise, among other noise sources, is appreciably more important since not only can it cause a degradation in these parameters but can cause entire chips to fail. Ensuring the integrity of the power supply voltage in the power distribution network of a chip is therefore crucial to both building reliable circuits as well as preventing circuit performance degradation. Power supply noise concerns, predicted over two decades ago, continue to draw significant attention, and with present CMOS technology projected to keep on scaling, it is shown in this work that these issues are not expected to diminish. This research also considers the management and on-chip detection of power supply noise. There are various methods of managing power supply noise, with the use of decoupling capacitors being the most common technique for suppressing the noise. An in-depth analysis of decap structures including scaling effects is presented in this work with corroborating silicon results. The applicability of various decaps for given design constraints is provided. It is shown that MOS-metal hybrid structures can provide a significant increase in capacitance per unit area compared to traditional structures and will continue to be an important structure as technology continues to scale. Noise suppression by means of current shifting within the clock period of an ALU block is further shown to be an additional method of reducing the minimum voltage observed on its associated supply. A simple, and area and power efficient technique for on-chip supply noise detection is also proposed