Luigia Micciullo

A novel emergency management platform for smart public safety

Summary This paper proposes an efficient architecture of a smart public safety platform that involves public professional operators as well as citizens. The proposed system is compliant with the emerging paradigm of a smart city. Its main features are that of monitoring, forecasting and managing emergency situations, arising from environmental disasters or crimes. The proposed platform performs a smart and functional integration of heterogeneous components as a smart data gathering and analysis system, a novel professional communication system, wireless sensor networks and social networks. Each element acts not only as an information collector but has autonomous capabilities to cooperate with the others in order to increase the system efficiency and to reduce the need of human interactions. Finally, the paper highlights some open research issues that represent critical aspects and require additional investigations in order to further improve the performance of the proposed platform. Copyright

LTE enhancements for public safety and security communications to support group multimedia communications

Currently public safety and security communication systems depend on reliable and secure PMR networks that are mainly devoted to provide voice services. However, the evolutionary trend for professional mobile radio (PMR) networks is toward the provision of new value-added multimedia services such as video streaming, in order to improve situational awareness and enhance life-saving operations. The challenge here is to exploit the future commercial broadband networks to deliver voice and multimedia services satisfying PMR service requirements. In particular, a viable solution now seems to be the adaption of the new Long Term Evolution technology to provide IP-based broadband services with the security and reliability typical of PMR networks. This article outlines different alternatives to achieve this goal and, in particular, proposes a proper solution for providing multimedia services with PMR standards over commercial LTE networks.

Public safety networks evolution toward broadband: sharing infrastructures and spectrum with commercial systems

Nowadays, efficient communication technologies are of paramount importance to provide effective and reliable emergency management systems. New wireless communications engineering approaches and value-added services could lead to great benefits, improving situational awareness and enhancing life-saving capabilities. For these reasons, governments and organizations involved in public safety and security (PSS) are devoting great interest in the transition from existing narrowband wireless systems toward broadband. For this purpose, a viable solution is to adapt the new LTE-A technology in order to provide IP-based broadband services with security and reliability characteristics typical of PSS networks. However, the migration of these systems to LTE-A is currently a critical issue. Costs, timing, and spectrum availability for the deployment of a PSS-dedicated network are demanding. In addition, providing mission-critical services on an LTE-based PSS system needs a proper network architecture solution in order to achieve and maintain required performance and reliability levels. To fully accomplish this task, research efforts can result in significant improvements and adjustments of future releases of the LTE-A standard. This article focuses on critical issues that impact PSS communications evolution toward new technologies and describes the related possible steps, starting from the exploitation of the already deployed LTE-A commercial networks up to a fully PSS-dedicated network infrastructure. Finally, advanced solutions are described and critically discussed.

An Efficient Subcarrier Allocation Method for AeroMACS-Based Communication Systems

The work presented here deals with an IEEE 802.16e-based system for airport surface communications, named AeroMACS. Such a system has been proposed as a possible solution to satisfy the growing demand of new communication services and needs of next generation air traffic management (ATM) systems. By focusing on a specific airport environment, a resource allocation algorithm is proposed that allows the communication system capacity to be increased by exploiting the tap correlation related to each user communication channel. Optimal resource allocation using tap correlation has been previously shown to have a significant gain with respect to different alternatives, but also suffers from severe computational complexity. In order to relax this drawback, a novel suboptimal method is proposed that allows the implementation complexity to be lowered and the derivation of channel parameters to be made affordable, in particular in the case of fast varying propagation conditions or high estimation latency. The performance of the proposed algorithm is validated by comparisons with those achieved by the optimal approach and alternative solutions under different application conditions and users speed values. The final result shown here is a significant performance improvement for the proposed algorithm with respect to standard alternatives.

A Novel Mitigation Scheme for JTIDS Impulsive Interference on LDACS System Based on Sensing and Symbol Retransmission

Future digital air/ground communication systems (LDACS) will operate on the L-Band where the coexistence with existing legacy systems shall be guaranteed. This paper proposes a scheme to detect and mitigate the JTIDS impulsive interference on LDACS-1 system. The novel idea advised here is the transmission of two copies of the symbols received with interference that are suitably combined at the receiver after a blanking operation of the corrupted samples. In particular two alternatives are presented that differ for the adopted retransmission policy, namely full combining scheme, where all the symbols are transmitted twice, and partial combining scheme, which foresees the retransmission of only those symbols where interference has been detected. Both these methods permit to efficiently remove the interference without affecting the useful information and exploiting profitably the diversity gain against noise through the soft combining approach. The numerical results provided in the paper highlight a good behavior of the proposed methods and significant advantages in comparison with the traditional blanking method, either in terms of Bit Error Rate and throughput.

A secure radio communication system based on an efficient speech watermarking approach

This paper deals with an efficient secure communication system based on a speech watermarking approach. The main goal of the system is to efficiently support air traffic control (ATC) communications by improving safety and security of the existing ATC equipment embedding digital side information into speech signals in order to allow an automatic identification of the talker. An implementation based on the use of the well known LPC (linear predictive coding) principle is discussed. The LPC residual is split up into voiced and unvoiced segments; while the voiced segments cross the system unmodified, the watermarking data are embedded into the unvoiced segments, spectrally similar to a white noise. The watermark signal is decoded by a very similar scheme. We provide also a statistical analysis on the unvoiced parts of the ATC communications that demonstrates the system feasibility. In addition to this, an optimization of the entire system has been also performed to increase performance. The obtained results highlight that the watermark data are nearly imperceptible and provide a data channel with rate from 2000 to 5000 kbits/s, with high robustness to channel noise; the system requires only modular, low-cost and easy-to-install encoders and decoders, maintaining compatibility with legacy RF DSB-AM transceivers. Moreover, it is well suited both for the actual 25 kHz RF channels and for the new 8.33 kHz European RF channels. Copyright

The Use of Social Networks in Emergency Management

Abstract: Nowadays people are used to going online to use a number of data sources, which provide information useful for their daily routine (status of transportation services, delay on commuters’ routes, traffic, weather etc.), as well as for leisure and social activities. At the same time, the availability of broadband connections allows mobile users to themselves become creators of online content, following the paradigm of Web 2.0. A large part of population is using social networks in their private life for sharing their daily experience through text or multimedia contents over several platforms with friends or even publically. Therefore, social networks represent a unique opportunity for bi-directional information exchange between a population and the authorities, acquiring a key role in emergency management. It is in fact possible to take advantage from a new “social awareness” of people that become in this way directly involved in crisis management by means of tools usually dedicate to recreational purposes. Official portals and institutional pages on social networks can be an efficient way to disseminate emergency alerts or information to large number of people. A quick advice dissemination is one of the most important things for reducing risks in disaster scenarios, and in many cases news is shared online by users before it is published on official portals; in particular the use of mobile devices increases the speed of information diffusion. Moreover, location-based applications can use information provided by official channels to show advice to citizens located in a particular emergency area and to assist them during rescue activities. This chapter describes how the collection of information posted on social media can make the difference in all emergency phases, and analyzes the available means which give citizens and authorities the possibility to accomplish their needs in emergency forecast, facing, management and response.

Old Buildings Broadband Home Networks: Technologies and Services Overview

Abstract Internet broadband access is becoming a reality in many countries. To fully exploit the benefits from high-speed connection, both suitable home network connectivity and advanced services support have to be made available to the user. In this article, issues relative to the upgrade of existing home networks, particularly in old buildings, together with networking and security requirements are addressed, and possible solutions are proposed.

Energy efficient cooperative multicast beamforming in ultra dense networks

Energy efficiency (EE) is one of the main requirements for future fifth generation wireless networks to allow a sustainable network development. Toward this goal, this study proposes a novel iterative algorithm to maximise the EE of multicast services in ultra dense networks. Macrocells and small cells cooperate using a multicast beamforming strategy to efficiently radiate the power in the considered area. Moreover, small cells are activated opportunistically, and their power levels are adjusted suitably. Due to the high complexity of the optimisation problem, the proposed algorithm works calculating iteratively beamforming weights and power adjustments, thus reducing the set of possible solutions. Then, an exhaustive search is performed among the elements of this restricted set. This solution has reduced computational complexity, and the achieved EE is higher than benchmark alternatives. Performance in terms of EE and complexity is provided together with a solution feasibility evaluation.

Interoperability for Public Safety Networks

It is widely recognized that efficient communications are of paramount importance in order to have effective Public Protection and Disaster Relief (PPDR) operations. Indeed, there is great interest from governments and organizations involved in PPDR toward the evolution of existing wireless systems for critical communications to have higher communication capacity. However, an efficient communication system depends also on the capability of providing service interoperability among different networks. Interoperability barriers among the communication systems of various PPDR organizations are present both at national level (among public safety organizations of the same region or nation) and among PPDR organizations from different nations. Interoperability barriers are usually based on historical reasons: communication networks are created by each PPDR organization with a vertical structure to address the specific requirement of the organization. In some cases, interoperability barriers are also due to security reasons. In an effort to secure and protect the network data, cryptography mechanism and cryptography keys are different even in networks based on the same technology. Interoperability barriers are more often operational than technical. Common procedures and organizational schemes during a national disaster may be defined at national level, but rarely at international level. Cross-border operations are particularly affected by lack of interoperability because of linguistic barriers or because national organizations use different network technologies. A critical issue is the lack of roaming capability, which is available for users of commercial networks (e.g. GSM/UMTS), but it is not available for the PPDR community. As a consequence, a PPDR officer moving from one dedicated PPDR network to another will lose the communication instead of being transferred to the new network.