Today mobile communications have evolved from merely connecting devices to enabling a wide range of heterogeneous services, particularly with 5G networks. The rise of multimedia services and digital content consumption is driving the proliferation of wireless devices, which in turn is increasing the complexity of resource management. In this scenario, a distributed system could be the most effective way to manage this complex environment for monitoring and support purposes, especially through Software Defined Radio (SDR) technology. This paper introduces a distributed SDR-based system designed to perform various services to monitor and support any mobile communication systems. After presenting the overall design of the proposed system, this work will describe and test a prototype that can execute a monitoring service for spectral analysis, interference detection, and localization.

In this paper, we propose a framework for cross-layer analysis of multi-static passive RFID systems. The model takes into account details of the shared wireless channel, including fading and capture effect, whereas, at the medium access control (MAC) layer, the anti-collision mechanism proposed in the EPC Generation 2 standard is taken as a reference. To address the complexity of the system model, we rely on a semi-analytical approach, that combines a moment matching approximation method to abstract the physical layer and Monte-Carlo simulations to describe the MAC dynamics. Furthermore, based on the space diversity feature offered by the multi-static settings, we introduce the concept ofcapture diversityand propose a modification to the standard to fully support this form of diversity. Numerical results show the impact of deployment conditions and the relative positions of interrogator, tags, and detection points on the performance of tags’ identification. We show how the number of detection points impacts the system performance under various channel conditions and MAC parameters’ settings. Finally, we validate the proposed update of the MAC protocol, showing substantial performance improvement with respect to the standard collision resolution policy.

In this paper, we propose a model for the analysis of distributed passive backscattering systems for Radio Frequency Identification with physically separated illuminator and reader. The model takes into account the physical channel characteristics including shadow fading components and thresholds for powering and detection. The dynamic framed ALOHA medium access mechanism defined by the EPC Global Generation 2 standard is considered to evaluate the performance. To address the complexity of the system model, our framework is based on a semi-analytical approach that combines moment matching approximation method at channel level and Monte-Carlo approach for the medium access control dynamics. Results show the impact of deployment conditions and the relative positions among illuminator, tags, and reader on the identification performance. Interestingly, the detection of the back-scattered signal at a remote reader can improve the performance with a higher probability of capture. However, as the distance increases, the impact of shadow fading counterpoises the capture effect. The resulting trade-off is accurately described by our model.

In this paper, we propose an equivalent channel model for the analysis of passive backscattering systems (e.g., Radio Frequency Identification systems). The proposed framework accurately models radiation efficiencies at the backscattering nodes whose communication channels are affected by spatially correlated shadowing. First, we derive the distribution of interference in the system and the probability that a node will activate as a function of a specific geographical distribution of the nodes. Then, we approximate the capture probability using a multivariate moment matching approach. The rationale is to provide an underlying structure for the cross-layer analysis of current MAC protocols with the perspective of performance enhancement. Numerical results illustrate the performance of a standard MAC protocol for passive RFID systems, including an accurate evaluation of the impact of the channel characterization.

The demonstration proposal moves from the capabilities of a wireless biometric badge [4], which integrates a localization and tracking service along with an automatic personal identification mechanism, to show how a full system architecture is devised to enable the control of physical accesses to restricted areas. The system leverages on the availability of a novel IEEE 802.15.4/Zigbee Cluster Tree network model, on enhanced security levels and on the respect of all the users' privacy issues.

The demo we propose represents a first step toward RF Sounding [1]. Such a project is an open space installation which comprises both artistic and technological innovations; its aim is to provide the user, while entering a specifically defined area, with awareness of radio frequency signals characterizing the cellular networks band. Indeed, radio signals are shifted, with proper elaboration, to the audible band and the result is spread all over the specific area through a certain number of loudspeakers. For this procedure we have been inspired by the eternal metaphor of the impossible human dream to fly, thus the limitations of our senses which are capable of feeling audio waves (sounds) but (maybe luckily) are not capable of directly feeling radio frequency (RF) waves are highlighted. The translation is the starting point for a more complex and exciting musical composition. It has to be underlined that some features of RF sensed signals are kept unchanged in order to give to the listener the clear feeling of the amount (power) of RF signals present in the monitored area. The aim of this project is twofold. Indeed, from one side we want to increase end users knowledge of the strength of the power emitted by their cellular phones with respect to the electromagnetic fields produced in the environment, on the other hand we want to provide for an artistic and interactive installation that can also be remotely joined through a web interface.

The demonstration proposal focuses on presenting the capabilities of a wireless biometric badge, which integrates a localization and tracking service along with an automatic personal identification mechanism, to control the access to restricted areas with a high level of security. The wireless biometric badge is the result of R&D activities conducted by several professors, researchers, and students in the Center of Excellence in Research DEWS at the University of L' Aquila in Italy, as well as its R&D Spin-Off WEST Aquila S.r.l.

This paper focuses on the analysis of fundamental issues which has to be considered in order to gain voice from a wireless sensor network (WSN) that is assumed to be constituted by MicaZ wireless sensor nodes. Problems related to the transport of an audio signal through a wireless channel and sensor nodes are thus analyzed and a project for an audio surveillance system is presented.