5,024 research outputs found
Active textile antennas in professional garments for sensing, localisation and communication
New wireless wearable monitoring systems integrated in professional garments require a high degree of reliability and autonomy. Active textile antenna systems may serve as platforms for body-centric sensing, localization and wireless communication systems, in the meanwhile being comfortable and invisible to the wearer. New design strategies combined with dedicated signal processing techniques greatly enhance the robustness of these systems. On the one hand, the large amount of real estate available in public regulated services' garments may be exploited to deploy multiple textile antennas. On the other hand, the size of each radiator may be designed large enough to ensure high radiation efficiency when deployed on the body. This antenna area is then reused by placing active electronics directly underneath and energy harvesters directly on top of the antenna patch. We illustrate this design paradigm by means recent textile antenna prototypes integrated in professional garments, providing sensing, positioning and communication capabilities
Programmable photonics : an opportunity for an accessible large-volume PIC ecosystem
We look at the opportunities presented by the new concepts of generic programmable photonic integrated circuits (PIC) to deploy photonics on a larger scale. Programmable PICs consist of waveguide meshes of tunable couplers and phase shifters that can be reconfigured in software to define diverse functions and arbitrary connectivity between the input and output ports. Off-the-shelf programmable PICs can dramatically shorten the development time and deployment costs of new photonic products, as they bypass the design-fabrication cycle of a custom PIC. These chips, which actually consist of an entire technology stack of photonics, electronics packaging and software, can potentially be manufactured cheaper and in larger volumes than application-specific PICs. We look into the technology requirements of these generic programmable PICs and discuss the economy of scale. Finally, we make a qualitative analysis of the possible application spaces where generic programmable PICs can play an enabling role, especially to companies who do not have an in-depth background in PIC technology
MH-60 Seahawk / MQ-8 Fire Scout interoperability
Approved for public release; distribution is unlimitedAs part of a Naval Postgraduate School's capstone project in Systems Engineering, a project team from Cohort 311-0911 performed a Systems Engineering analysis. This Project focused on defining alternatives for enhanced Anti-Surface Warfare (ASUW) mission effectiveness through increased interoperability and integration for the Fire Scout Unmanned Air Vehicle and Seahawk helicopter. Specifically, the Project explored the available trade space for enhancing communications back to the ship for analysis and decision-making. Modeling and Simulation (MandS) was used to assess the impact of enhanced communication on specific Key performance Parameters (KPPs) and Measures of Effectiveness (MOEs) associated with the ASUW mission. Once the trade space was defined, alternatives were analyzed and a recommendation provided that supports near-, mid-, and long-term mission enhancement
Managing big data experiments on smartphones
The explosive number of smartphones with ever growing sensing and computing capabilities have brought a paradigm shift to many traditional domains of the computing field. Re-programming smartphones and instrumenting them for application testing and data gathering at scale is currently a tedious and time-consuming process that poses significant logistical challenges. Next generation smartphone applications are expected to be much larger-scale and complex, demanding that these undergo evaluation and testing under different real-world datasets, devices and conditions. In this paper, we present an architecture for managing such large-scale data management experiments on real smartphones. We particularly present the building blocks of our architecture that encompassed smartphone sensor data collected by the crowd and organized in our big data repository. The given datasets can then be replayed on our testbed comprising of real and simulated smartphones accessible to developers through a web-based interface. We present the applicability of our architecture through a case study that involves the evaluation of individual components that are part of a complex indoor positioning system for smartphones, coined Anyplace, which we have developed over the years. The given study shows how our architecture allows us to derive novel insights into the performance of our algorithms and applications, by simplifying the management of large-scale data on smartphones
How Rapid is Rapid Prototyping? Analysis of ESPADON Programme Results
New methodologies, engineering processes, and support environments are beginning to emerge for embedded signal processing systems. The main objectives are to enable defence industry to field state-of-the-art products in less time and with lower costs, including retrofits and upgrades, based predominately on commercial off the shelf (COTS) components and the model-year concept. One of the cornerstones of the new methodologies is the concept of rapid prototyping. This is the ability to rapidly and seamlessly move from functional design to the architectural design to the implementation, through automatic code generation tools, onto real-time COTS test beds. In this paper, we try to quantify the term “rapid†and provide results, the metrics, from two independent benchmarks, a radar and sonar beamforming application subset. The metrics show that the rapid prototyping process may be sixteen times faster than a conventional process
Reconfigurable Reflectarrays and Array Lenses for Dynamic Antenna Beam Control: A Review
Advances in reflectarrays and array lenses with electronic beam-forming
capabilities are enabling a host of new possibilities for these
high-performance, low-cost antenna architectures. This paper reviews enabling
technologies and topologies of reconfigurable reflectarray and array lens
designs, and surveys a range of experimental implementations and achievements
that have been made in this area in recent years. The paper describes the
fundamental design approaches employed in realizing reconfigurable designs, and
explores advanced capabilities of these nascent architectures, such as
multi-band operation, polarization manipulation, frequency agility, and
amplification. Finally, the paper concludes by discussing future challenges and
possibilities for these antennas.Comment: 16 pages, 12 figure
Parallel netCDF: A Scientific High-Performance I/O Interface
Dataset storage, exchange, and access play a critical role in scientific
applications. For such purposes netCDF serves as a portable and efficient file
format and programming interface, which is popular in numerous scientific
application domains. However, the original interface does not provide an
efficient mechanism for parallel data storage and access. In this work, we
present a new parallel interface for writing and reading netCDF datasets. This
interface is derived with minimum changes from the serial netCDF interface but
defines semantics for parallel access and is tailored for high performance. The
underlying parallel I/O is achieved through MPI-IO, allowing for dramatic
performance gains through the use of collective I/O optimizations. We compare
the implementation strategies with HDF5 and analyze both. Our tests indicate
programming convenience and significant I/O performance improvement with this
parallel netCDF interface.Comment: 10 pages,7 figure
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