29 research outputs found
Distributed Apportioning in a Power Network for providing Demand Response Services
Greater penetration of Distributed Energy Resources (DERs) in power networks
requires coordination strategies that allow for self-adjustment of
contributions in a network of DERs, owing to variability in generation and
demand. In this article, a distributed scheme is proposed that enables a DER in
a network to arrive at viable power reference commands that satisfies the DERs
local constraints on its generation and loads it has to service, while, the
aggregated behavior of multiple DERs in the network and their respective loads
meet the ancillary services demanded by the grid. The Net-load Management
system for a single unit is referred to as the Local Inverter System (LIS) in
this article . A distinguishing feature of the proposed consensus based
solution is the distributed finite time termination of the algorithm that
allows each LIS unit in the network to determine power reference commands in
the presence of communication delays in a distributed manner. The proposed
scheme allows prioritization of Renewable Energy Sources (RES) in the network
and also enables auto-adjustment of contributions from LIS units with lower
priority resources (non-RES). The methods are validated using
hardware-in-the-loop simulations with Raspberry PI devices as distributed
control units, implementing the proposed distributed algorithm and responsible
for determining and dispatching realtime power reference commands to simulated
power electronics interface emulating LIS units for demand response.Comment: 7 pages, 11 Figures, IEEE International Conference on Smart Grid
Communication
WiMAX Basics From Deployments to PHY Improvements
漏 ASEE 2014WiMAX (Worldwide Interoperability for Microwave Access) is an emerging broadband wireless technology for providing Last mile solutions for supporting higher bandwidth and multiple service classes with various quality of service requirement. The unique architecture of the WiMAX MAC and PHY layers that uses OFDMA to allocate multiple channels with different modulation schema and multiple time slots for each channel allows better adaptation of heterogeneous user鈥檚 requirements. The main architecture in WiMAX uses PMP (Point to Multipoint), Mesh mode or the new MMR (Mobile Multi hop Mode) deployments where scheduling and multicasting have different approaches. In PMP SS (Subscriber Station) connects directly to BS (Base Station) in a single hop route so channel conditions adaptations and supporting QoS for classes of services is the key points in scheduling, admission control or multicasting, while in Mesh networks SS connects to other SS Stations or to the BS in a multi hop routes, the MMR mode extends the PMP mode in which the SS connects to either a relay station (RS) or to Bs. Both MMR and Mesh uses centralized or distributed scheduling with multicasting schemas based on scheduling trees for routing. In this paper a broad study is conducted About WiMAX technology PMP and Mesh deployments from main physical layers features with differentiation of MAC layer features to scheduling and multicasting approaches in both modes of operations
A Secure Key Management Model for Wireless Mesh Networks
As Wireless Mesh Networks (WMNs) are newly emerging wireless technologies, they are designed to have huge potential for strengthening Internet deployment and access. However, they are far from muture for large-scale deployment in some applications due to the lack of the satisfactory guarantees on security. The main challenges exposed to the security of WMNs come from the facts of the shared nature of the wireless architecture and the lack of globally trusted central authorities. A well-performed security framework for WMNs will contribute to network survivability and strongly support the network growth. A low-computational and scalable key management model for WMNs is proposed in this paper which aims to guarantee well-performed key management services and protection from potential attacks
Non-repudiable authentication and billing architecture for wireless mesh networks
Wireless mesh networks (WMNs) are a kind of wireless ad hoc networks
that are multi-hop where packets are forwarded from source to destination
by intermediate notes as well as routers that form a kind of network infrastructure
backbone. We investigate the security of the recently proposed first known secure
authentication and billing architecture for WMNs which eliminates the need for
bilateral roaming agreements and that for traditional home-foreign domains. We
show that this architecture does not securely provide incontestable billing contrary
to designer claims and furthermore it does not achieve entity authentication. We
then present an enhanced scheme that achieves entity authentication and nonrepudiable
billing
WIMAX Basics from PHY Layer to Scheduling and Multicasting Approaches
WiMAX (Worldwide Interoperability for Microwave Access) is an emerging broadband wireless technology for providing Last mile solutions for supporting higher bandwidth and multiple service classes with various quality of service requirement. The unique architecture of the WiMAX MAC and PHY layers that uses OFDMA to allocate multiple channels with different modulation schema and multiple time slots for each channel allows better adaptation of heterogeneous user鈥檚 requirements. The main architecture in WiMAX uses PMP (Point to Multipoint), Mesh mode or the new MMR (Mobile Multi hop Mode) deployments where scheduling and multicasting have different approaches. In PMP SS (Subscriber Station) connects directly to BS (Base Station) in a single hop route so channel conditions adaptations and supporting QoS for classes of services is the key points in scheduling, admission control or multicasting, while in Mesh networks SS connects to other SS Stations or to the BS in a multi hop routes, the MMR mode extends the PMP mode in which the SS connects to either a relay station (RS) or to Bs. Both MMR and Mesh uses centralized or distributed scheduling with multicasting schemas based on scheduling trees for routing. In this paper a broad study is conducted About WiMAX technology PMP and Mesh deployments from main physical layers features with differentiation of MAC layer features to scheduling and multicasting approaches in both modes of operations
An Electronic Health Application for Disaster Recovery
Natural disasters often destroy the fixed wired communications infrastructure. Therefore relying on such infrastructure after a catastrophe can be risky. Wireless Mesh Networks (WMNs) can provide wireless network coverage without relying on a wired backbone infrastructure or dedicated access points. In this paper, we focus on using WMNs in disaster recovery areas in order to disseminate information from patient to doctors. We investigate whether we can deploy an electronic-health application on top of an ad hoc peer to peer network. The initial prototype shows that it is feasible. However the application quality varies depending on the number of multi-hops and the applications concurrently running on top of the WMN networks
PLATAFORMA METEOROL脫GICA DE BAJO COSTO BASADA EN TECNOLOG脥A ZIGBEE
Este trabajo presenta el dise帽o, desarrollo e implementaci贸n de una plataforma meteorol贸gica de bajo costo, que incluye un sistema de comunicaci贸n basada en tecnolog铆a ZigBee para el monitoreo remoto. Para esto se ha utilizado una tarjeta de desarrollo basada en el microcontrolador Atmega2560 con tarjetas deaplicaci贸n/ampliaci贸n orientados a aplicaciones de obtenci贸n de datos y conectividad. Se incorpora una tarjeta electr贸nica Arduino Ethernet para crear un entorno de programaci贸n que permiti贸 la visualizaci贸n de datos de las variables obtenidas en tiempo real
Bandwidth Allocation Based on Traffic Load and Interference in IEEE 802.16 Mesh Networks
This paper introduces a traffic load and interference based bandwidth allocation (TLIBA) scheme for wireless mesh network (WMN) that improves the delay and throughput performance by proper utilization of assigned bandwidth. The bandwidth is allocated based jointly on traffic load and interference. Then a suitable path is selected based upon the least routing metric (RM) value. Simulation results are presented to demonstrate the effectiveness of the proposed approach which indicates higher bandwidth utilization and throughput as compared with existing fair end-to-end bandwidth allocation (FEBA)