Radio Link Design Framework for WSN Deployment and Performance Prediction

To address the needs of Cyber Physical System applications, and particularly for an easy implementation of wireless sensor and actuator networks (WSAN), semiconductor companies are offering single-chip solutions embedding in the same device a microcontroller core with a wireless transceiver. These internet-on-chip devices support different connections [1-4]: Bluetooth, ZigBee and Bluetooth Low Energy at 2.4 GHz, Wi-Fi at 5 GHz, sub-GHz ISM (Industrial, Scientific, Medical) at 868/915 MHz or 315/433 MHz. The used microcontroller cores range from 8-bit 8051 for low-power short-range solutions to 32-bit Cortex-M ARM ones. The max. sustained bit-rates are from 250 kb/s (sub-GHz links) to 4 Mb/s (Wi-Fi). For example, in case of TI cc254x and cc31xx devices, there are different trade-offs between receiver sensitivity (from -74 dBm to -100 dBm) and maximum transmitter power (from 0 dBm to 5 dBm). These performance parameters lead to different link distances, but also to different power consumption levels, from few mW to several hundreds of mW. A range extender device can be added [5] to improve RX noise figure (down to 4.7 dB) and TX power (up to 22 dBm), although for a power overhead of 480 mW

Design Exploration of mm-Wave Integrated Transceivers for Short-Range Mobile Communications Towards 5G

This paper presents a design exploration, at both system and circuit levels, of integrated transceivers for the upcoming fifth generation (5G) of wireless communications. First, a system level model for 5G communications is carried out to derive transceiver design specifications. Being 5G still in pre-standardization phase, a few currently used standards (ECMA-387, IEEE 802.15.3c, and LTE-A) are taken into account as the reference for the signal format. Following a top-down flow, this work presents the design in 65nm CMOS SOI and bulk technologies of the key blocks of a fully integrated transceiver: low noise amplifier (LNA), power amplifier (PA) and on-chip antenna. Different circuit topologies are presented and compared allowing for different trade-offs between gain, power consumption, noise figure, output power, linearity, integration cost and link performance. The best configuration of antenna and LNA co-design results in a peak gain higher than 27dB, a noise figure below 5dB and a power consumption of 35mW. A linear PA design is presented to face the high Peak to Average Power Ratio (PAPR) of multi-carrier transmissions envisaged for 5G, featuring a 1dB compression point output power (OP1dB) of 8.2dBm. The delivered output power in the linear region can be increased up to 13.2dBm by combining four basic PA blocks through a Wilkinson power combiner/divider circuit. The proposed circuits are shown to enable future 5G connections, operating in a mm-wave spectrum range (spanning 9GHz, from 57GHz to 66GHz), with a data-rate of several Gb/s in a short-range scenario, spanning from few centimeters to tens of meters

Energy-efficient link resource allocation in the multibeam satellite downlink under QoS constraints

The paper proposes a novel adaptive coding and modulation scheme, based on DVB-S2X standard, which ensure very high spectral efficiency, and an energy-efficient power control (PC) algorithm to optimize the goodput over a multibeam satellite downlink. Results show performance improvement whenand compared withto conventional PC approaches based on rate satisfaction

Cross-layer link adaptation for goodput optimization in MIMO BIC-OFDM systems

This work proposes a novel cross-layer link performance prediction (LPP) model and link adaptation (LA) strategy for soft-decoded multiple-input multiple-output (MIMO) bit-interleaved coded orthogonal frequency division multiplexing (BIC-OFDM) systems employing hybrid automatic repeat request (HARQ) protocols. The derived LPP, exploiting the concept of effective signal-to-noise ratio mapping (ESM) to model system performance over frequency-selective channels, does not only account for the actual channel state information at the transmitter and the adoption of practical modulation and coding schemes (MCSs), but also for the effect of the HARQ mechanism with bit-level combining at the receiver. Such method, named aggregated ESM, or αESM for short, exhibits an accurate performance prediction combined with a closed-form solution, enabling a flexible LA strategy, that selects at every protocol round the MCS maximizing the expected goodput (EGP), i.e., the number of correctly received bits per unit of time. The analytical expression of the EGP is derived capitalizing on the αESM and resorting to the renewal theory. Simulation results carried out in realistic wireless scenarios corroborate our theoretical claims and show the performance gain obtained by the proposed αESM-based LA strategy when compared with the best LA algorithms proposed so far for the same kind of systems

Rainfall Map from Attenuation Data Fusion of Satellite Broadcast and Commercial Microwave Links

The demand for accurate rainfall rate maps is growing ever more. This paper proposes a novel algorithm to estimate the rainfall rate map from the attenuation measurements coming from both broadcast satellite links (BSLs) and commercial microwave links (CMLs). The approach we pursue is based on an iterative procedure which extends the well-known GMZ algorithm to fuse the attenuation data coming from different links in a three-dimensional scenario, while also accounting for the virga phenomenon as a rain vertical attenuation model. We experimentally prove the convergence of the procedures, showing how the estimation error decreases for every iteration. The numerical results show that adding the BSL links to a pre-existent CML network boosts the accuracy performance of the estimated rainfall map, improving up to 50% the correlation metrics. Moreover, our algorithm is shown to be robust to errors concerning the virga parametrization, proving the possibility of obtaining good estimation performance without the need for precise and real-time estimation of the virga parameters

Marconi e l'innovativo parco antenne di Coltano

Tra la fine del 1902 e l’inizio del 1903, Guglielmo Marconi manifesto' la sua intenzione di costruire una potente stazione radiotelegrafica intercontinentale in Italia ed avvio' per questo scopo dei contatti con le autorita' italiane. L’intento originario di Marconi, illustrato anche al re Vittorio Emanuele III, era quello di costruire una stazione radio “ultra potente” (cioe' concepita per servizi intercontinentali), in grado di collegare l’Italia con il Sud America. Tuttavia, questo ambizioso obiettivo venne presto abbandonato, probabilmente a causa della difficolta' tecnica di una trasmissione wireless su una così grande distanza e la stazione venne quindi proposta per fornire collegamenti radio con l’America del Nord e le colonie italiane nell’Africa Orientale. Per apprezzare quanto fosse innovativo questo progetto di Marconi, basti ricordare che nel 1903, esistevano nel Mondo solo tre stazioni ultra potenti: una in Gran Bretagna, una negli Stati Uniti ed una in Canada

Liquid chromatography tandem mass spectrometry analysis of synthetic coccidiostats in eggs

Coccidiostats are synthetic drugs administered to animals, especially to poultry, to cure coccidiosis. In this paper, we present a selective liquid chromatography-tandem mass spectrometry (LC-MS/MS) method to analyze residues of five synthetic coccidiostats in eggs: clazuril, diclazuril, robenidine, nicarbazin, toltrazuril and its two metabolites. The extraction efficiency was evaluated by testing several solvents, pH, different volumes and time of extraction. The clean-up procedures were optimized using different solid phase extraction cartridges and different eluants. The chromatographic separation was achieved in reversed phase using a gradient of 0.1% formic acid in water and acetonitrile, whereas the MS detection was performed in negative electrospray ionization (ESI) for all the analytes, except for the robenidine. The developed method has been validated according to Commission Decision 2002/657/CE. The validation parameters, as linearity, precision, recovery, specificity, decision limit (CC alpha), detection capability (CC beta), and robustness have been determined. The proposed method resulted simple, fast, and suitable for screening and confirmation purposes

Joint Latency-Energy Minimization for Fog-Assisted Wireless IoT Networks

This work aims to present a joint resource allocation method for a fog-assisted network wherein IoT wireless devices simultaneously offload their tasks to a serving fog node. The main contribution is to formulate joint minimization of service latency and energy consumption objectives subject to both radio and computing constraints. Moreover, unlike previous works that set a fixed value to the circuit power dissipated to operate a wireless device, practical models are considered. To derive the Pareto boundary between two conflicting objectives we consider, Tchebyshev theorem is used for each wireless device. The competition among devices is modeled using the cooperative Nash bargaining solution and its unique cooperative Nash equilibrium (NE) is computed based on block coordinate descent algorithm. Numerical results obtained using realistic models are presented to corroborate the effectiveness of the proposed algorithm

Exploiting mm-wave communications to boost the performance of industrial wireless networks

This work explores the potentiality of millimeter waves (mmW) as physical layer in industrial wireless networks. Innovative models and a link design method are proposed to achieve reliable communication, at a distance of tens of meters for a single hop, even in harsh environments. By exploiting the worldwide-free band of several GHz, available around 60 GHz, mmW links allow to achieve a performance boosting of up to two orders of magnitude, w.r.t. conventional sub-6-GHz wireless links, in indoor industrial environments. Time slotted channel hopping and frequency-diversity can be implemented with a large number of channels, and with high bit rate (several Mb/s per channel). This allows for robust networking of high data-rate sensors, such as cameras, radars, or laser scanners. Featuring a low bit error rate, mmW communication allows for low-latency link and large number of hops in networks with a large radius. Finally, it ensures interference separation from operating frequencies of electrical machines, switching converters, and other industrial wireless networks (e.g., 802.11 or 802.15). Implementation results for key HWblocks in low-cost technologies show the feasibility of mmW communication nodes with low-power and compact size

Software-Defined Radio Technologies forGNSS Receivers: A Tutorial Approach to a SimpleDesign and Implementation

The field of satellite navigation has witnessed the advent of a number of new systems and technologies: after the landmark design and development of the Global Positioning System (GPS), a number of new independent Global Navigation Satellite Systems (GNSSs) were or are being developed all over the world: Russia's GLONASS, Europe's GALILEO, and China's BEIDOU-2, to mention a few. In this ever-changing context, the availability of reliable and flexible receivers is becoming a priority for a host of applications, including research, commercial, civil, and military. Flexible means here both easily upgradeable for future needs and/or on-the-fly reprogrammable to adapt to different signal formats. An effective approach to meet these design goals is the software-defined radio (SDR) paradigm. In the last few years, the availability of new processors with high computational power enabled the development of (fully) software receivers whose performance is comparable to or better than that of conventional hardware devices, while providing all the advantages of a flexible and fully configurable architecture. The aim of this tutorial paper is surveying the issue of the general architecture and design rules of a GNSS software receiver, through a comprehensive discussion of some techniques and algorithms, typically applied in simple PC-based receiver implementations