Wireless characterization and assessment of an UWB-Based system in industrial environments

The advent of Indsutrial Internet of Things is one of the main drivers for the implementation of Industry 4.0 scenarios and applications, in which wireless communication systems play a key role in terms of flexibility, mobility and deployment capabilities. However, the integration of wireless communication systems poses challenges, owing to variable path loss conditions and interference impact. In this work, an Ultra-Wideband (UWB) system for indoor location in very large, complex industrial scenarios is presented. Precise wireless channel characterization for the complete volume of a logistical plant is performed, based on 3D hybrid ray launching approximation, in order to aid network node design process. Wireless characterization, implementation and measurement results are obtained for both 4 GHz and 6 GHz frequency bands, considering different densities of scatterers within the scenario under test. Time domain estimation results have been obtained and compared with time of flight measurement results, showing good agreement. The proposed methodology enables to perform system design and performance tasks, analyzing the impact of variable object density conditions in wireless channel response, providing accurate time of flight estimations without the need of complex channel sounder systems, aiding in optimal system planning and implementation.This work was supported in part by the European Union’s Horizon 2020 Research and Innovation Programme (Stardust-Holistic and Integrated Urban Model for Smart Cities) under Grant 774094, in part by the Ministerio de Ciencia through the Innovación y Universidades, Gobierno de España (Agencia Estatal de Investigación, Fondo Europeo de Desarrollo Regional—FEDER, European Union) under Grant RTI2018-095499-B-C31 IoTrain, and in part by the Gobierno de Navarra-Departamento de Desarrollo Económico under Grant 0011-1365-2019-000097 OEE LOG

Impact of polarization diversity in massive MIMO for industry 4.0

The massive polarimetric radio channel is evaluated in an indoor industrial scenario at 3.5 GHz using a 10×10 uniform rectangular array (URA). The analysis is based on (1) propagation characteristics like the average received gain and the power to interference ratio from the Gram matrix and (2) system-oriented metrics such as sum-rate capacity with maximum-ratio transmitter (MRT). The results clearly show the impact of polarization diversity in an industrial scenario and how it can considerably improve different aspects of the system design. Results for sum-rate capacity are promising and show that the extra degree of freedom, provided by polarization diversity, can optimize the performance of a very simple precoder, the MRT

EC-CENTRIC: An Energy- and Context-Centric Perspective on IoT Systems and Protocol Design

The radio transceiver of an IoT device is often where most of the energy is consumed. For this reason, most research so far has focused on low power circuit and energy efficient physical layer designs, with the goal of reducing the average energy per information bit required for communication. While these efforts are valuable per se, their actual effectiveness can be partially neutralized by ill-designed network, processing and resource management solutions, which can become a primary factor of performance degradation, in terms of throughput, responsiveness and energy efficiency. The objective of this paper is to describe an energy-centric and context-aware optimization framework that accounts for the energy impact of the fundamental functionalities of an IoT system and that proceeds along three main technical thrusts: 1) balancing signal-dependent processing techniques (compression and feature extraction) and communication tasks; 2) jointly designing channel access and routing protocols to maximize the network lifetime; 3) providing self-adaptability to different operating conditions through the adoption of suitable learning architectures and of flexible/reconfigurable algorithms and protocols. After discussing this framework, we present some preliminary results that validate the effectiveness of our proposed line of action, and show how the use of adaptive signal processing and channel access techniques allows an IoT network to dynamically tune lifetime for signal distortion, according to the requirements dictated by the application

Polarimetric properties of indoor MIMO channels for different floor levels in a residential house

This paper analyzes polarimetric characteristics of power delay profiles (PDPs), cross polarization discrimination (XPD), and received power of specular and diffuse multipath components of indoor MIMO radio channels at 2.45 GHz. Measurements were done in a residential house at two floors levels: "same floor" and "cross floor". Variations of 5 to 15 dB in PDPs between co-and cross-polar links were found in the same floor level; however these changes decrease as radio links move from line-of-sight to non-line-of-sight propagations. XPDs of radio waves were found to be higher for cross floor configuration, about 5 dB in horizontally and 7 dB in vertically polarized waves. Also, diffuse components of channels were less affected compared to that of specular components in same floor setups for cross-polar links. Our results demonstrate that the contribution of diffuse components to total channel power is higher than previously presented studies for large industrial indoor environments