Cosecant-Squared Radiation Pattern Surface Wave Antenna for Millimeter-wave FMCW Vertical-Looking Radar System

This work presents our preliminary work on an electric field (E-field) prediction technique and near-field tofar-field transformation of a surface wave antenna with a cosecant-squared pattern for a millimeter-wave FMCW vertical-looking radar system. Fourier and Gaussian fitting models were used to predict the magnitude and phase of E-field on the antenna surface, and the prediction error at the center operating frequency of 34.5 GHz are 4.6% and 4.6° respectively. The far-field E-plane pattern was achieved by applying Fourier Transform to the predicted near-field E-field distribution

An improved wireless communication fabric for emerging Network-on-Chip design

Existing wireless communication interface has free space signal radiation which drastically reduces the received signal strength and hence reduces the throughput efficiency of Hybrid Wired-Wireless Network-on-Chip (WiNoC). This paper addresses the issue of throughput degradation by replacing the wireless layer of WiNoCs with a novel Complementary Metal Oxide Semiconductor (CMOS) based waveguide communication fabric that is able compete with the reliability of traditional wired NoCs. A combination of a novel transducer and a commercially available thin metal conductor coated with a low cost Taconic Taclamplus dielectric material is presented to generate surface wave signals with high signal integrity. Our experimental results demonstrate that, the proposed communication fabric can achieve a 5 dB operational bandwidth of about 60 GHz around the center frequency (60 GHz). Compared to existing WiNoCs, the proposed communication fabric a performance improvement of 13.8% and 10.7% in terms of throughput and average packet delay, respectively. Specifically, under realistic traffic patterns, the average packet latency can be reduced by 30% when the mm-Wave is replaced by the proposed communication fabric

On the Gain and Link Equation for Reactive Millimetre-wave Surface Wave Propagation System

Surface-wave has been proven to be the third option between wired and wireless communication. It has been proposed to be utilised for inter-machine and on-body communications, because of its on-surface two-dimensional feature. It provides a flexible two-dimensional platform and shows many advantages such as power savings, excellent electromagnetic compatibility characteristic, non-line-of-sight communication over traditional space wave wireless communication systems. When compared to wired systems, surface wave systems can provide a wide band channel for one-to-many/many-to-one communications. This work we will demonstrate our recent work in the concept of surface wave gain and formulate the surface wave wireless link equation for the first time. A 52 GHz 3-dB bandwidth test bed was constructed to validate the theoretical and simulation results in the proposed method and equation

Thermal and Performance Efficient On-Chip Surface-Wave Communication for Many-Core Systems in Dark Silicon Era

Due to the exceedingly high integration density of VLSI circuits and the resulting high power density, thermal integrity became a major challenge. One way to tackle this problem is Dark silicon. Dark silicon is the amount of circuitry in a chip that is forced to switch off to insure thermal integrity of the system and prevent permanent thermal-related faults. In many-core systems, the presence of Dark Silicon adds new design constraints, in general, and on the communication fabric of such systems, in particular. This is due to the fact that system-level thermal-management systems tend to increase the distance between high activity cores to insure better thermal balancing and integrity. Consequently, a designing dilemma is created where a compromise has to be made between interconnect performance and power consumption. This study proposes a hybrid wire and surface-wave interconnect (SWI) based Network-on-Chip (NoC) to address the dark silicon challenge. Through efficient utilization of one-hop cross the chip communication SWI links, the proposed architecture is able to offer an efficient and scalable communication platform in terms of performance, power, and thermal impact. As a result, evaluations of the proposed architecture compared to baseline architecture under dark silicon scenarios show reduction in maximum temperature by 15°C, average delay up to 73.1%, and energy-saving up to ~3X. This study explores the promising potential of the proposed architecture in extending the utilization wall for current and future many-core systems in dark silicon era

Simulation and Experimental Verification for a 52 GHz Wideband Trapped Surface Wave Propagation System

Trapped surface wave (TSW) provides a flexible 2-D wireless solution when compared to existing wired and free space communications systems. This work aims to provide the theoretical guidance, supported by simulation techniques and experimental verifications, for 1) designing the wideband and highly efficient rectangular aperture TSW transducers and 2) selecting the best reactive surface impedance for high efficiency. First, a method for computing the TSW excitation efficiency is proposed for the first time and it can be applied to different kinds of reactive surface geometries and transducer apertures. Then, the relation between the TSW excitation efficiency, surface reactance, and aperture height is derived. Then, the maximum excitation efficiency, the corresponding optimal surface reactance, and aperture height are presented. Furthermore, the relation between the TSW angular coverage and aperture width is determined. These studies show that the aperture height mainly determines the TSW excitation efficiencies, while the aperture width controls the TSW angular coverage; hence, the two aperture parameters of a transducer can be independently determined. Finally, an experiment setup, based on the provided guidelines, has been built to demonstrate a 52 GHz wide 3 dB-transmission-bandwidth for high-performance communications systems

mHealth Engineering: A Technology Review

In this paper, we review the technological bases of mobile health (mHealth). First, we derive a component-based mHealth architecture prototype from an Institute of Electrical and Electronics Engineers (IEEE)-based multistage research and filter process. Second, we analyze medical databases with regard to these prototypic mhealth system components.. We show the current state of research literature concerning portable devices with standard and additional equipment, data transmission technology, interface, operating systems and software embedment, internal and external memory, and power-supply issues. We also focus on synergy effects by combining different mHealth technologies (e.g., BT-LE combined with RFID link technology). Finally, we also make suggestions for future improvements in mHealth technology (e.g., data-protection issues, energy supply, data processing and storage)

A Novel Technique Enabling the Realisation of 60 GHz Body Area Networks

This paper presents a novel technique to enable over-body propagation at 60 GHz. A flexible material has been created that enables the propagation of surface waves around the body without the need of repeaters, high powers or high gain antennas. The solution is wireless and self-redundant, and will facilitate the development of light weight, high bandwidth, and low power, wireless body area networks that could offer improvements for mobile health monitoring applications as well as utility in sports and entertainment industries. © 2012 IEEE

Switched-Beam 60 GHz Endfire Circular Patch Planar Array With Integrated 2-D Butler Matrix for Chip-to-Chip Space-Surface Wave Communications

The complexity of chip interconnection on a multicore multichip (MCMC) module using the traditional wired interconnects increases with the chip count. The global wired interconnects that run across the entire module must be made longer as more chips are placed on a larger module. Since the interconnect delay grows as the square of the interconnect length, the global wired interconnects can become a major bottleneck of the computing performance in such systems. This dissertation presents a new type of hybrid space-surface wave interconnect (HSSW-I) using 60 GHz switched-beam antenna arrays to provide high-speed communication between the chips. The antennas communicate at near the speed of light through radiation in the air above the chips and through surface waves at the air-dielectric interface, and thus avoid lengthy delays. Each array consists of four center-fed circular patch elements with side vias in a 2 × 2 planar grid arrangement. The arrays enable multi-gigabits-per-second (Gbps) reconfigurable interchip communication when integrated with the proper chip transceivers. The main beam of the array is switched in the horizontal plane containing the chips, by changing the interelement phase shifts. The switching of the main beam is analyzed and verified through full-wave simulation. A compact two-dimensional (2-D) Butler matrix feed network is designed, implemented, and integrated with the circular patch planar array. The matrix is a four-input, four-output, i.e., 4 × 4 network consisting of four interconnected quadrature (90°) hybrid couplers and allows endfire scanning of the array main beam along the four diagonal directions in the horizontal plane. The realized antenna module is a thin multilayer microstrip (MS) structure with a footprint small enough to fit over a typical multicore chip. The antenna module provides a seamless and practical way to achieve reconfigurable interchip communication in MCMC systems. A multiantenna module (MAM) consisting of five antenna modules that emulates diagonal interchip communication in MCMC systems is fabricated. The simulation and measurement of the transmission coefficients between the antenna modules on the MAM are performed, and the signal-to-noise ratio (SNR) and signal-to-noise-plus-interference ratio (SNIR) of the links are calculated. A link decomposition simulation technique to determine the relative contribution of space and surface waves is also applied. A transmission link model is devised based on the leaky wave effect shown by the antenna arrays and the model coefficients are determined from the simulation data. The link model is then extrapolated at various distances and compared with more measurement and simulation results for verification. Finally, realistic link budget calculations are performed based on the measured and simulated data. The calculations show that the antenna modules using the HSSW-I can achieve raw data transfer rates up to 42.24 Gbps at 20 mm distance with low bit error rates (BERs) in the absence of interference, when used with the state-of-the-art 60 GHz complementary metal oxide semiconductor (CMOS) transceivers

Interconnects architectures for many-core era using surface-wave communication

PhD ThesisNetworks-on-chip (NoCs) is a communication paradigm that has emerged aiming to address on-chip communication challenges and to satisfy interconnection demands for chip-multiprocessors (CMPs). Nonetheless, there is continuous demand for even higher computational power, which is leading to a relentless downscaling of CMOS technology to enable the integration of many-cores. However, technology downscaling is in favour of the gate nodes over wires in terms of latency and power consumption. Consequently, this has led to the era of many-core processors where power consumption and performance are governed by inter-core communications rather than core computation. Therefore, NoCs need to evolve from being merely metalbased implementations which threaten to be a performance and power bottleneck for many-core efficiency and scalability. To overcome such intensified inter-core communication challenges, this thesis proposes a novel interconnect technology: the surface-wave interconnect (SWI). This new RF-based on-chip interconnect has notable characteristics compared to cutting-edge on-chip interconnects in terms of CMOS compatibility, high speed signal propagation, low power dissipation, and massive signal fan-out. Nonetheless, the realization of the SWI requires investigations at different levels of abstraction, such as the device integration and RF engineering levels. The aim of this thesis is to address the networking and system level challenges and highlight the potential of this interconnect. This should encourage further research at other levels of abstraction. Two specific system-level challenges crucial in future many-core systems are tackled in this study, which are cross-the-chip global communication and one-to-many communication. This thesis makes four major contributions towards this aim. The first is reducing the NoC average-hop count, which would otherwise increase packet-latency exponentially, by proposing a novel hybrid interconnect architecture. This hybrid architecture can not only utilize both regular metal-wire and SWI, but also exploits merits of both bus and NoC architectures in terms of connectivity compared to other general-purpose on-chip interconnect architectures. The second contribution addresses global communication issues by developing a distance-based weighted-round-robin arbitration (DWA) algorithm. This technique prioritizes global communication to be send via SWI short-cuts, which offer more efficient power dissipation and faster across-the-chip signal propagation. Results obtained using a cycleaccurate simulator demonstrate the effectiveness of the proposed system architecture in terms of significant power reduction, considervii able average delay reduction and higher throughput compared to a regular NoC. The third contribution is in handling multicast communications, which are normally associated with traffic overload, hotspots and deadlocks and therefore increase, by an order of magnitude the power consumption and latency. This has been achieved by proposing a novel routing and centralized arbitration schemes that exploits the SWI0s remarkable fan-out features. The evaluation demonstrates drastic improvements in the effectiveness of the proposed architecture in terms of power consumption ( 2-10x) and performance ( 22x) but with negligible hardware overheads ( 2%). The fourth contribution is to further explore multicast contention handling in a flexible decentralized manner, where original techniques such as stretch-multicast and ID-tagging flow control have been developed. A comparison of these techniques shows that the decentralized approach is superior to the centralized approach with low traffic loads, while the latter outperforms the former near and after NoC saturation

The Lateral Confinement of Microwave Surface Waves

Surface waves and their applications have been extensively studied by the photonics and radio engineering communities throughout the whole of the twentieth century. This thesis details briefly the history of both approaches and highlights their signi cance with regard to the subject of this thesis; laterally confining a surface wave in the microwave regime. Detailed within are the experimental, analytical and numerical methods used to ascertain what, if any, effect a change in the dimension of a guiding structure has on the dispersion of a mode supported by a metamaterial. The method of experimentally determining the dispersion of a microwave surface wave is discussed. The insensitivity of a mode supported on a one-dimensional corrugated array to the lateral width of the supporting array, even when the width is much less than the wavelength of radiation incident upon it, is investigated. Spatial dependent reduction of group velocity associated with a microwave surface wave is also detailed. Local electric-field and phase measurements are used to probe this condition. In particular, the measurement of phase associated with the supported microwave surface wave is shown to indicate the trapping location of a surface wave more accurately when compared to local electric-field measurement. The channelling of surface waves via the addition of dielectric overlayers to a metamaterial surface is investigated. By progressively narrowing the width of the channel, the interaction of the electric fields associated with the mode supported in the channel with the bordering dielectric overlayer increases. This investigation leads to a discussion of the electric field overlap between two regions of differing surface impedance.EPSR