Hybrid analog-digital processing system for amplitude-monopulse RSSI-based MiMo wifi direction-of-arrival estimation

We present a cost-effective hybrid analog digital system to estimate the Direction of Arrival (DoA) of WiFi signals. The processing in the analog domain is based on simple wellknown RADAR amplitude monopulse antenna techniques. Then, using the RSSI (Received Signal Strength Indicator) delivered by commercial MiMo WiFi cards, the DoA is estimated using the socalled digital monopulse function. Due to the hybrid analog digital architecture, the digital processing is extremely simple, so that DoA estimation is performed without using IQ data from specific hardware. The simplicity and robustness of the proposed hybrid analog digital MiMo architecture is demonstrated for the ISM 2.45GHz WiFi band. Also, the limitations with respect to multipath effects are studied in detail. As a proof of concept, an array of two MiMo WiFi DoA monopulse readers are distributed to localize the two-dimensional position of WiFi devices. This costeffective hybrid solution can be applied to all WiFi standards and other IoT narrowband radio protocols, such us Bluetooth Low Energy or Zigbee.This work was supported in part by the Spanish National Projects TEC2016-75934-C4-4-R, TEC2016-76465-C2-1-R and in part by Regional Seneca Project 19494/PI/14

Despliege de redes inalambricas de entornos industriales

This document discusses the potential of wireless technologies in solving many of the problems found in an industrial environment, where a reliable communication network is needed but a wired system fails to meet all the requirements imposed by such a harsh environment. After a brief review of industrial networks, the requirements of an industrial environment and some emerging wireless technologies of interest, a particular application scenario is shown: applying wireless technologies to a shipyard.Este trabajo ha sido parcialmente financiado por el proyecto nacional FAR-IP (TIC2000-1734-C03-03)

OBIWAN: wireless sensor networks with OMNET++

Simulation is essential in WSN study. However, the nature of WSN makes it an unexpectedly complex task. The extremely large number of nodes, the need for an environment model, and the cross-layer dependencies of the models are some of the reasons for this complexity. Many of the existing simulation tools do not properly handle these issues. In this paper, OBIWAN, a new simulator for WSN is presented. In its design, critical issues like reusability, scalability and cross-layer dependencies have been addressed. The results on its capabilities and performance are provided through a case study involving several thousand nodes and an environment modelThis, work has been funded by the Economy,Industry and Innovation Council,with the SOLIDMOVIL project(2I04SU044),by Fundación Séneca both from the Region of Murcia with the ARENA Project(00546/PI/04)and by the Spanish Research Council with the ARPaq project(TEC2004-05622-C04-02/TCM)and CSI-RHET project(TEC2005-08068–C04-01/TCM)

An IEEE 802.11 protocol test-bed in industrial environments using personal computing devices

IEEE 802.11 is being currently considered to develop telecommunications infrastructures in industrial environments. However, in such environments there may exist a high level of electromagnetic fields (EMF) contamination, due to the machinery in use. Wireless LANs are sensitive to this type of hazard, and therefore the performance of the protocols may be affected inside the industrial facilities. In this paper we conduct a study of the wireless link performance in these industrial scenarios, using personal computing devices. Such equipments will be likely used by employees rather than conventional computers. Since the results do not characterize the environment itself, but the set of environment and hardware, a proper measurement test-bed must include direct measurements with these devices. Besides, due to limitations in these equipments, a specific protocol to measure pairs of packet error probability and latency is also developed. Results reveal a significant linear dependency between both magnitudes, and a large correlation coefficient in the measurements under high EMF activity at mid-large ranges (distances greater than 5 meters)This work has been cofunded by the Economy,Industry and Innovation Council,with the SOLIDMOVIL project(2I04SU044),supported by Fundación Séneca,from the Región of Murcia with the ARENA Project(00546/PI/04),and by the Spanish Research Council with the ARPaq project(TEC2004-05622-C04-02/TCM)and the CSI-RHE Tproject(TEC2005-08068-C04-01/TCM)

RSSI-Based direction-of-departure estimation in bluetooth low energy using an array of frequency-steered leaky-wave antennas

This paper presents a novel advanced Bluetooth Low Energy (BLE) beacon, which is based on an array of frequency-steered leaky-wave antennas (LWAs), as a transmitter for a Direction-of-Departure (DoD) estimation system. The LWA array is completely passive, fabricated in a low-cost FR4 printed-circuit board and designed to multiplex to different angular directions in space each one of the three associated BLE advertising channels that are used for periodically transmitting the ID of the beacon. This way, the use of more expensive hardware associated to electronic phased-array steering/beam-switching is avoided. Four commercial BLE modules are connected to the four ports of the array, producing an advanced BLE beacon that synthesizes twelve directive beams (one per each port and advertising channel) distributed over a wide Field of View (FoV) of 120 degrees in the azimuthal plane. Then, any BLE enabled IoT device located within this FoV can scan the messages from the beacon and obtain the corresponding Received Signal Strength Indicator (RSSI) of these twelve beams to estimate the relative DoD by using amplitude-monopulse signal processing, thus dispensing from complex In-phase/Quadrature (IQ) data acquisition or high computational load.We propose an angular windowing technique to eliminate angular ambiguities and increase the angular resolution, reporting a root mean squared angular error of 3.7º in a wide FoV of 120º.This work was supported in part by the Spanish National projects TEC2016-75934-C4-4-R and TEC2016-76465-C2-1-R, and in part by the 2018 UPCT Santander Research Grant

Performance evaluation of non-persistent CSMA as anti-collision protocol for active RFID tags.

In this paper we propose the use of non-persistent CSMA as an anti-collision procedure for RFID active tags. Current proposals for both passive and active tags are based on the framed slotted ALOHA protocol, which does not scale well requiring additional procedures for frame length adaptation. However, active RFID devices already include carrier sense capabilities with no additional cost and, thus, CSMA may be employed seamlessly. Nevertheless, selecting the contention micro-slots of CSMA in the classical way (i.e., with a uniform distribution and an exponential back-off algorithm) does not result in an efficient identification process, as we will demonstrate. Fortunately, better choices can be found. Recently, an optimal distribution for the selection of micro-slots for event-driven sensor networks has been computed, as well as a practical implementation: the Sift distribution. In this work we propose the application of the quasi-optimal Sift distribution along with CSMA for active tag identification. By means of an analytical study, we evaluate the average time needed for identification with this mechanism and compare it with the current ISO 18000-7 and EPC “Gen 2” standard. The results reveal that the Sift-based non-persistent CSMA outperforms both of them. Moreover, it also scales much better, without the need for further adaptation mechanismsThis work has been funded by the Spanish Ministerio de Educación y Ciencia with the projects DEP2006-56158-C03-03/EQUI and m:ciudad (FIT-330503- 2006-2, partially funded by ERDF) and by the Spanish Research Council with the ARPaq project (TEC2004-05622-C04-02/TCM)

Sistemas de localización e identificación para el sector logístico y de servicios

La presentación nos muestra la inclusión de las nuevas tecnologías en todos los modos de transporte, su diseño e implantación de tecnologías ITS, ( Sistemas Inteligentes de Transportes).Fundación Séneca. Ministerio de Educación y Ciencia. Fondo Social Europeo

A wireless sensor networks MAC protocol for real-time applications.

Wireless Sensor Networks (WSN) are designed for data gathering and processing, with particular requirements: low hardware complexity, low energy consumption, special traffic pattern support, scalability, and in some cases, real-time operation. In this paper we present the Virtual TDMA for Sensors (VTS) MAC protocol, which intends to support the previous features, focusing particularly on real-time operation. VTS adaptively creates a TDMA arrangement with a number of timeslots equal to the actual number of nodes in range. Thus, VTS achieves an optimal throughput performance compared to TDMA protocols with fixed size of frame. The frame is set up and maintained by a distributed procedure, which allows sensors to asynchronously join and leave the frame. In addition, duty cycle is increased or decreased in order to keep latency constant below a given deadline. Therefore, a major advantage of VTS is that it guarantees a bounded latency, which allows soft real-time applications.This work has been cofunded by the Economy, Industry and Innovation Council, with the SOLIDMOVIL project (2I04SU044), supported by Fundacion Seneca, from the Region of Murcia with the ARENA Project (00546/PI/04), with the ARPaq project (TEC2004-05622-C04-02/TCM) by the Spanish Research Council and the CSI-RHET project (TEC2005-08068-C04-01/TCM)

Development of a control system for teleoperated robots using UML nd Ada 95

In this paper, a control system in the domain of teleoperated service robots is presented. A reference architecture - ACROSET - has been analyzed and designed following a concurrent object modeling and architectural design methodology (COMET) that uses UML as describing language. The architecture of the whole system has been implemented in a ship’s hull blasting robot - GOYA –using Ada 95 and GLADE. Our previous experience in developing teleoperated service robots using Ada is also presente

MEGAESTAND: plataforma telemática para la gestión de palets reutilizables en la cadena de suministro mediante tecnología RFID

La empresa ECOMOVISTAND ha patentado un palet ecológico y reutilizable, denomimado M.T., orientado al sector de la distribución y la logística. Es necesario un sistema logístico novedoso e innovador que no está disponible en la actualidad y que requiere controlar y saber en qué punto del circuito logístico se encuentra un M.T. de forma automática. Para lograr la localización sin necesidad de intervención humana, un M.T. tiene que integrar una tecnología de bajo coste que genere de forma automática flujos de información. Para tal fin, el Grupo de Ingeniería Telemática ha desarrollado el sistema RFID activo SOLIDMOVIL formado por tags RFID integrados en un M.T. y lectores RFID. que se sitúan en puntos estratégicos del circuito logístico. En el presente artículo se presenta la plataforma telemática MEGAESTAND, basada en una arquitectura de servicios web, que sirve para el control de la trazabilidad de los M.T’s mediante una red de lectores RFID que se comunican mediante GPRS con el Centro Logístico. A su vez, mediante la plataforma MEGAESTAND se tiene la infraestructura tecnológica para que ECOMOVISTAND desarrolle y ofrezca servicios de valor añadido a sus clientes: control de entrada y salida de pedidos, trazabilidad de productos para consumo humano, control de la cadena de frío y otros.Este trabajo ha sido financiado por un contrato de I+D con la empresa ECOMOVISTAN