Automated routing and control of silicon photonic switch fabrics

Automatic reconfiguration and feedback controlled routing is demonstrated in an 8×8 silicon photonic switch fabric based on Mach-Zehnder interferometers. The use of non-invasive Contactless Integrated Photonic Probes (CLIPPs) enables real-time monitoring of the state of each switching element individually. Local monitoring provides direct information on the routing path, allowing an easy sequential tuning and feedback controlled stabilization of the individual switching elements, thus making the switch fabric robust against thermal crosstalk, even in the absence of a cooling system for the silicon chip. Up to 24 CLIPPs are interrogated by a multichannel integrated ASIC wire-bonded to the photonic chip. Optical routing is demonstrated on simultaneous WDM input signals that are labelled directly on-chip by suitable pilot tones without affecting the quality of the signals. Neither preliminary circuit calibration nor lookup tables are required, being the proposed control scheme inherently insensible to channels power fluctuations

Internet of Hybrid Energy Harvesting Things

© 2017 IEEE. Internet of Things (IoT) is a perfect candidate to realize efficient observation and management for Smart City concept. This requires deployment of large number of wireless devices. However, replenishing batteries of thousands, maybe millions of devices may be hard or even impossible. In order to solve this problem, Internet of Energy Harvesting Things (IoEHT) is proposed. Although the first studies on IoEHT focused on energy harvesting (EH) as an auxiliary power provisioning method, now completely battery-free and self-sufficient systems are envisioned. Taking advantage of diverse sources that the concept of Smart City offers helps us to fully appreciate the capacity of EH. In this way, we address the primary shortcomings of IoEHT; availability, unreliability, and insufficiency by the Internet of Hybrid EH Things (IoHEHT). In this paper, we survey the various EH opportunities, propose an hybrid EH system, and discuss energy and data management issues for battery-free operation. We mathematically prove advantages of hybrid EH compared to single source harvesting as well. We also point out to hardware requirements and present the open research directions for different network layers specific to IoHEHT for Smart City concept

Modeling the controlled delivery power grid

Competitive energy markets, stricter regulation, and the integration of distributed renewable energy sources are forcing companies to reengineer energy production and distribution. The Controlled Delivery Power Grid is proposed as a novel approach to transport energy from generators to consumers. In this approach, energy distribution is performed in an asynchronous and distributed fashion. Much like the Internet, energy is delivered as addressable packets, which allow a controlled delivery of energy. As a proof-of-concept of the controllable delivery grid, two experimental test beds, one with integrated energy storage and another with no energy storage, were designed and built to evaluate the efficiency of a power distribution and scheduling scheme. Both test beds use a request-grant protocol where energy is supplied in discrete quantities. The performance of the system is measured in terms of the ability to satisfy requests from consumers. The results show high satisfaction ratios for distribution capacities that are smaller than the maximum demand. The distribution of energy is modelled with graph theory and as an Integer Linear Programming problem to minimize transmission losses and determine routes for energy flows in a network with distributed sources and consumers. The obtained results are compared with a heuristic approach based on the Dijkstra\u27s shortest path algorithm, which is proposed as a feasible approach to routing the transmission of packetized energy