Results for "Petar Popovski"

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Zero-Error Capacity of a Class of Timing ChannelsNov 06 2013Aug 24 2014We analyze the problem of zero-error communication through timing channels that can be interpreted as discrete-time queues with bounded waiting times. The channel model includes the following assumptions: 1) Time is slotted, 2) at most $ N $ "particles" ... More
On Buffer-Aided Multiple-Access Relay ChannelSep 21 2016Sep 22 2016The paper treats uplink scenario where M user equipments (UEs) send to a Base Station (BS), possibly via a common Relay Station (RS) that is equipped with a buffer. This is a multiple-access relay channel (MARC) aided by a buffer. We devise a protocol ... More
Towards Massive, Ultra-Reliable, and Low-Latency Wireless Communication with Short PacketsApr 24 2015Mar 01 2016Most of the recent advances in the design of high-speed wireless systems are based on information-theoretic principles that demonstrate how to efficiently transmit long data packets. However, the upcoming wireless systems, notably the 5G system, will ... More
Analysis of LoRaWAN Uplink with Multiple Demodulating Paths and Capture EffectFeb 07 2019Low power wide area networks (LPWANs), such as the ones based on the LoRaWAN protocol, are seen as enablers of large number of IoT applications and services. In this work, we assess the scalability of LoRaWAN by analyzing the frame success probability ... More
Wirelessly Powered Communication Networks with Short PacketsOct 24 2016Wirelessly powered communications will entail short packets due to naturally small payloads, low-latency requirements and/or insufficient energy resources to support longer transmissions. In this paper, a wirelessly powered communication system is investigated ... More
Coded Random Access: How Coding Theory Helps to Build Random Access ProtocolsMay 16 2014The rise of machine-to-machine communications has rekindled the interest in random access protocols and their use to support a massive number of uncoordinatedly transmitting devices. The classic ALOHA approach is developed under a collision model, where ... More
Ultra-Reliable Communication in 5G Wireless SystemsOct 16 2014Wireless 5G systems will not only be "4G, but faster". One of the novel features discussed in relation to 5G is Ultra-Reliable Communication (URC), an operation mode not present in today's wireless systems. URC refers to provision of certain level of ... More
Delayed Channel State Information: Incremental Redundancy with Backtrack RetransmissionJan 27 2014In many practical wireless systems, the Signal-to-Interference-and-Noise Ratio (SINR) that is applicable to a certain transmission, referred to as Channel State Information (CSI), can only be learned after the transmission has taken place and is thereby ... More
On Wirelessly Powered Communications with Short PacketsSep 16 2016Wireless-powered communications will entail short packets due to naturally small payloads, low latency requirements and/or insufficient energy resources to support longer transmissions. In this paper, a wireless-powered communication system is investigated ... More
Efficient Blockchain Synchronization for Internet of Things using Signature AmortizationApr 15 2019Apr 18 2019We study the problem of efficiently disseminating authenticated blockchain information from blockchain nodes (servers) to Internet of Things (IoT) devices, through a wireless base station (BS). In existing blockchain protocols, upon generation of a new ... More
Two-Way Communication with Energy ExchangeApr 09 2012The conventional assumption made in the design of communication systems is that the energy used to transfer information between a sender and a recipient cannot be reused for future communication tasks. A notable exception to this norm is given by passive ... More
Wireless Secrecy in Cellular Systems with Infrastructure--Aided CooperationMay 03 2008In cellular systems, confidentiality of uplink transmission with respect to eavesdropping terminals can be ensured by creating intentional inteference via scheduling of concurrent downlink transmissions. In this paper, this basic idea is explored from ... More
Why to Decouple the Uplink and Downlink in Cellular Networks and How To Do ItMar 23 2015Ever since the inception of mobile telephony, the downlink and uplink of cellular networks have been coupled, i.e. mobile terminals have been constrained to associate with the same base station (BS) in both the downlink and uplink directions. New trends ... More
On the Impact of Wireless Jamming on the Distributed Secondary Microgrid ControlSep 22 2016The secondary control in direct current microgrids (MGs) is used to restore the voltage deviations caused by the primary droop control, where the latter is implemented locally in each distributed generator and reacts to load variations. Numerous recent ... More
Protocol Coding through Reordering of User Resources: Applications and Capacity ResultsNov 26 2010Feb 01 2012While there are continuous efforts to introduce new communication systems and standards, it is legitimate to ask the question: how can one send additional bits by minimally changing the systems that are already operating? This is of a significant practical ... More
ALOHA Random Access that Operates as a Rateless CodeAug 07 2013Various applications of wireless Machine-to-Machine (M2M) communications have rekindled the research interest in random access protocols, suitable to support a large number of connected devices. Slotted ALOHA and its derivatives represent a simple solution ... More
A Random Access Protocol for Pilot Allocation in Crowded Massive MIMO SystemsApr 14 2016The Massive MIMO (multiple-input multiple-output) technology has a great potential to manage the rapid growth of wireless data traffic. Massive MIMO achieve tremendous spectral efficiency by spatial multiplexing of many tens of user equipments (UEs). ... More
Start Making Sense: Semantic Plane Filtering and Control for Post-5G ConnectivityJan 18 2019This is a short position paper that introduces the concepts of semantic plane filtering and control for post-5G connectivity.
Coded Slotted ALOHA with Varying Packet Loss Rate across UsersJun 29 2013The recent research has established an analogy between successive interference cancellation in slotted ALOHA framework and iterative belief-propagation erasure-decoding, which has opened the possibility to enhance random access protocols by utilizing ... More
Protocol Coding through Reordering of User Resources, Part I: Capacity ResultsFeb 01 2012The vast existing wireless infrastructure features a variety of systems and standards. It is of significant practical value to introduce new features and devices without changing the physical layer/hardware infrastructure, but upgrade it only in software. ... More
Network Slicing for Ultra-Reliable Low Latency Communication in Industry 4.0 ScenariosAug 30 2017An important novelty of 5G is its role in transforming the industrial production into Industry 4.0. Specifically, Ultra-Reliable Low Latency Communications (URLLC) will, in many cases, enable replacement of cables with wireless connections and bring freedom ... More
What Can Wireless Cellular Technologies Do about the Upcoming Smart Metering Traffic?Feb 04 2015Jul 01 2015The introduction of smart electricity meters with cellular radio interface puts an additional load on the wireless cellular networks. Currently, these meters are designed for low duty cycle billing and occasional system check, which generates a low-rate ... More
Coverage and Rate of Downlink Sequence Transmissions with Reliability GuaranteesApr 18 2017Jun 24 2017Real-time distributed control is a promising application of 5G in which communication links should satisfy certain reliability guarantees. In this letter, we derive closed-form maximum average rate when a device (e.g. industrial machine) downloads a sequence ... More
Physical Network Coding in Two-Way Wireless Relay ChannelsJul 03 2007It has recently been recognized that the wireless networks represent a fertile ground for devising communication modes based on network coding. A particularly suitable application of the network coding arises for the two--way relay channels, where two ... More
Capacity Analysis of Decoupled Downlink and Uplink Access in 5G Heterogeneous SystemsOct 27 2014Our traditional notion of a cell is changing dramatically given the increasing degree of heterogeneity in 4G and emerging 5G systems. Rather than belonging to a specific cell, a device would choose the most suitable connection from the plethora of connections ... More
Reliable Reception of Wireless Metering Data with Protocol CodingMay 21 2013Stationary collectors reading wireless, battery powered smart meters, often operate in harsh channel conditions to cut network installation cost to a minimum, challenging the individual link to each meter. The desired performance measure is reliable reception ... More
Massive MIMO for Internet of Things (IoT) ConnectivityMay 15 2019Massive MIMO is considered to be one of the key technologies in the emerging 5G systems, but also a concept applicable to other wireless systems. Exploiting the large number of degrees of freedom (DoFs) of massive MIMO essential for achieving high spectral ... More
Reliable Uplink Communication through Double Association in Wireless Heterogeneous NetworksMay 08 2015Apr 03 2016We investigate methods for network association that improve the reliability of uplink transmissions in dense wireless heterogeneous networks. The stochastic geometry analysis shows that the double association, in which an uplink transmission is transmitted ... More
Low-Rate Machine-Type Communication via Wireless Device-to-Device (D2D) LinksMay 29 2013Wireless cellular networks feature two emerging technological trends. The first is the direct Device-to-Device (D2D) communications, which enables direct links between the wireless devices that reutilize the cellular spectrum and radio interface. The ... More
Zero-Outage Cellular Downlink with Fixed-Rate D2D UnderlayApr 28 2014Dec 30 2014Two of the emerging trends in wireless cellular systems are Device-to-Device (D2D) and Machine-to-Machine (M2M) communications. D2D enables efficient reuse of the licensed spectrum to support localized transmissions, while M2M connections are often characterized ... More
Generalized HARQ Protocols with Delayed Channel State Information and Average Latency ConstraintsJan 22 2018In many wireless systems, the signal-to-interference-and-noise ratio that is applicable to a certain transmission, referred to as channel state information (CSI), can only be learned after the transmission has taken place and is thereby delayed (outdated). ... More
Latency Analysis of Systems with Multiple Interfaces for Ultra-Reliable M2M CommunicationMay 07 2016One of the ways to satisfy the requirements of ultra-reliable low latency communication for mission critical Machine-type Communications (MTC) applications is to integrate multiple communication interfaces. In order to estimate the performance in terms ... More
Network-Assisted Device-to-Device (D2D) Direct Proximity Discovery with Underlay CommunicationAug 13 2015Device-to-Device communications are expected to play an important role in current and future cellular generations, by increasing the spatial reuse of spectrum resources and enabling lower latency communication links. This paradigm has two fundamental ... More
Minimizing the Age of Information from Sensors with Correlated ObservationsNov 15 2018The Age of Information (AoI) metric has recently received much attention as a measure of freshness of information in a network. In this paper, we study the average AoI in a generic setting with correlated sensor information, which can be related to multiple ... More
Minimizing the Age of Information from Sensors with Common ObservationsNov 15 2018Mar 19 2019We study the average Age of Information (AoI) in a system where physical sources produce independent discrete-time updates that are each observed by several sensors. We devise a model that is simple, but still capable to capture the main tradeoffs. Two ... More
Downlink Transmission of Short Packets: Framing and Control Information RevisitedMay 06 2016Cellular wireless systems rely on frame-based transmissions. The frame design is conventionally based on heuristics, consisting of a frame header and a data part. The frame header contains control information that provides pointers to the messages within ... More
Block-Fading Channels with Delayed CSIT at Finite BlocklengthJan 28 2014In many wireless systems, the channel state information at the transmitter (CSIT) can not be learned until after a transmission has taken place and is thereby outdated. In this paper, we study the benefits of delayed CSIT on a block-fading channel at ... More
Random Access Protocols with Collision Resolution in a Noncoherent SettingSep 29 2014Dec 29 2014Wireless systems are increasingly used for Machine-Type Communication (MTC), where the users sporadically send very short messages. In such a setting, the overhead imposed by channel estimation is substantial, thereby demanding noncoherent communication. ... More
Sign-Compute-Resolve for Random AccessSep 24 2014We present an approach to random access that is based on three elements: physical-layer network coding, signature codes and tree splitting. Upon occurrence of a collision, physical-layer network coding enables the receiver to decode the sum of the information ... More
Analysis of LT Codes with Unequal Recovery TimeApr 20 2012In this paper we analyze a specific class of rateless codes, called LT codes with unequal recovery time. These codes provide the option of prioritizing different segments of the transmitted data over other. The result is that segments are decoded in stages ... More
Design and Analysis of LT Codes with Decreasing Ripple SizeNov 09 2010Jun 07 2012In this paper we propose a new design of LT codes, which decreases the amount of necessary overhead in comparison to existing designs. The design focuses on a parameter of the LT decoding process called the ripple size. This parameter was also a key element ... More
Sign-Compute-Resolve for Tree Splitting Random AccessFeb 08 2016We present an approach to random access that is based on three elements: physical-layer network coding (PLNC), signature codes and tree splitting. In presence of a collision, physical-layer network coding enables the receiver to decode, i.e. compute the ... More
Optimized Interface Diversity for Ultra-Reliable Low Latency Communication (URLLC)Dec 14 2017An important ingredient of the future 5G systems will be Ultra-Reliable Low-Latency Communication (URLLC). A way to offer URLLC without intervention in the baseband/PHY layer design is to use \emph{interface diversity} and integrate multiple communication ... More
Decoupled Uplink and Downlink in a Wireless System with Buffer-Aided RelayingSep 21 2016Sep 22 2016The paper treats a multiuser relay scenario where multiple user equipments (UEs) have a two-way communication with a common Base Station (BS) in the presence of a buffer-equipped Relay Station (RS). Each of the uplink (UL) and downlink (DL) transmission ... More
Reliable and Efficient Access for Alarm-initiated and Regular M2M Traffic in IEEE 802.11ah SystemsJun 29 2017EEE 802.11ah is a novel WiFi-based protocol, aiming to provide an access solution for the machine-to-machine (M2M) communications. In this paper, we propose an adaptive access mechanism that can be seamlessly incorporated into IEEE 802.11ah protocol operation ... More
Power Talk for Multibus DC MicroGrids: Creating and Optimizing Communication ChannelsSep 26 2016We study a communication framework for nonlinear multibus DC MicroGrids based on a deliberate modification of the parameters of the primary control and termed power talk. We assess the case in which the information is modulated in the deviations of reference ... More
Sign-Compute-Resolve for Tree Splitting Random AccessFeb 08 2016May 16 2018We present a framework for random access that is based on three elements: physical-layer network coding (PLNC), signature codes and tree splitting. In presence of a collision, physical-layer network coding enables the receiver to decode, i.e. compute, ... More
Inter-plane satellite matching in dense LEO constellationsMay 21 2019Dense constellations of Low Earth Orbit (LEO) small satellites are envisioned to extend the coverage of IoT applications via the inter-satellite link (ISL). Within the same orbital plane, the inter-satellite distances are preserved and the links are rather ... More
Coexistence of URLLC and eMBB services in the C-RAN Uplink: An Information-Theoretic StudyApr 18 2018The performance of orthogonal and non-orthogonal multiple access is studied for the multiplexing of enhanced Mobile BroadBand (eMBB) and Ultra-Reliable Low-Latency Communications (URLLC) users in the uplink of a multi-cell Cloud Radio Access Network (C-RAN) ... More
Minimizing Latency to Support VR Social Interactions over Wireless Cellular Systems via Bandwidth AllocationFeb 09 2018Apr 04 2018Immersive social interactions of mobile users are soon to be enabled within a virtual space, by means of virtual reality (VR) technologies and wireless cellular systems. In a VR mobile social network, the states of all interacting users should be updated ... More
5G Ultra-Reliable Vehicular CommunicationOct 05 2015Oct 08 2015Applications enabled by Cooperative Intelligent Transport Systems (C-ITS) represent a major step towards making the road transport system safer and more efficient (green), and thus suited for a sustainable future. Wireless communication between vehicles ... More
Using Wireless Network Coding to Replace a Wired with Wireless BackhaulApr 14 2014Cellular networks are evolving towards dense deployment of small cells. This in turn demands flexible and efficient backhauling solutions. A viable solution that reuses the same spectrum is wireless backhaul where the Small Base Station (SBS) acts as ... More
Physical Layer Network Coding: A Cautionary Story with Interference and Spatial ReservationNov 06 2013Physical layer network coding (PLNC) has the potential to improve throughput of multi-hop networks. However, most of the works are focused on the simple, three-node model with two-way relaying, not taking into account the fact that there can be other ... More
A Pseudo-Bayesian Approach to Sign-Compute-Resolve Slotted ALOHAJun 29 2017Access reservation based on slotted ALOHA is commonly used in wireless cellular access. In this paper we investigate its enhancement based on the use of physical-layer network coding and signature coding, whose main feature is enabling simultaneous resolution ... More
Modemless Multiple Access Communications over Powerlines for DC Microgrid ControlSep 14 2016We present a communication solution tailored specifically for DC microgrids (MGs) that exploits: (i) the communication potential residing in power electronic converters interfacing distributed generators to powerlines and (ii) the multiple access nature ... More
Reengineering GSM/GPRS Towards a Dedicated Network for Massive Smart MeteringOct 24 2014GSM is a synonym for a major success in wireless technology, achieving widespread use and high technology ma- turity. However, its future is questionable, as many stakeholders indicate that the GSM spectrum should be refarmed for LTE. On the other hand, ... More
Reliable Reporting for Massive M2M Communications with Periodic Resource PoolingApr 04 2014This letter considers a wireless M2M communication scenario with a massive number of M2M devices. Each device needs to send its reports within a given deadline and with certain reliability, e. g. 99.99%. A pool of resources available to all M2M devices ... More
Protocol Coding through Reordering of User Resources, Part II: Practical Coding StrategiesFeb 01 2012We use the term protocol coding to denote the communication strategies in which information is encoded through the actions taken by a certain communication protocol. In this work we investigate strategies for protocol coding via combinatorial ordering ... More
Frameless ALOHA Protocol for Wireless NetworksMay 18 2012Oct 10 2012We propose a novel distributed random access scheme for wireless networks based on slotted ALOHA, motivated by the analogies between successive interference cancellation and iterative belief-propagation decoding on erasure channels. The proposed scheme ... More
Delay Minimization in Real-time Communications with Joint Buffering and CodingOct 14 2016We present a closed-form expression for the minimal delay that is achievable in a setting that combines a buffer and an erasure code, used to mitigate the packet delay variance. The erasure code is modeled according to the recent information-theoretic ... More
A Statistical Learning Approach to Ultra-Reliable Low Latency CommunicationSep 14 2018Mission-critical applications require Ultra-Reliable Low Latency (URLLC) wireless connections, where the packet error rate (PER) goes down to $10^{-9}$. Fulfillment of the bold reliability figures becomes meaningful only if it can be related to a statistical ... More
Frameless ALOHA with Reliability-Latency GuaranteesSep 07 2017One of the novelties brought by 5G is that wireless system design has increasingly turned its focus on guaranteeing reliability and latency. This shifts the design objective of random access protocols from throughput optimization towards constraints based ... More
On a User-Centric Base Station Cooperation Scheme for Reliable CommunicationsMar 02 2017In this paper, we describe CoMP2flex, a user-centric base station (BS) cooperation scheme that provides improvements in reliability of both uplink (UL) and downlink (DL) communications of wireless cellular networks. CoMP2flex supports not only cooperation ... More
Delivery Latency Trade-Offs of Heterogeneous Contents in Fog Radio Access NetworksJan 23 2017Apr 18 2017A Fog Radio Access Network (F-RAN) is a cellular wireless system that enables content delivery via the caching of popular content at edge nodes (ENs) and cloud processing. The existing information-theoretic analyses of F-RAN systems, and special cases ... More
Cognitive Access-Transmission Policies under a Primary ARQ process via Chain DecodingSep 26 2015This paper introduces a novel technique that enables access by a cognitive secondary user (SU) to a spectrum occupied by an incumbent primary user (PU) that employs Type-I Hybrid ARQ. The technique allows the SU to perform selective retransmissions of ... More
Efficient LTE Access with Collision Resolution for Massive M2M CommunicationsOct 24 2014LTE random access procedure performs satisfactorily in case of asynchronous, uncorrelated traffic arrivals. However, when the arrivals are correlated and arrive synchronously, the performance of the random access channel (RACH) is drastically reduced, ... More
Analysis of the Decoupled Access for Downlink and Uplink in Wireless Heterogeneous NetworksJul 02 2014Oct 21 2014Wireless cellular networks evolve towards a heterogeneous infrastructure, featuring multiple types of Base Stations (BSs), such as Femto BSs (FBSs) and Macro BSs (MBSs). A wireless device observes multiple points (BSs) through which it can access the ... More
Efficiency Analysis of Decoupled Downlink and Uplink Access in Heterogeneous NetworksDec 04 2014This paper analyzes two-tier heterogeneous cellular network with decoupled downlink and uplink access. The basic performance benefits of uplink/downlink decoupling have been recently introduced. Here we provide a more elaborate treatment of the decoupling ... More
A Study of Trade-off between Opportunistic Resource Allocation and Interference Alignment in Femtocell ScenariosApr 20 2012One of the main problems in wireless heterogeneous networks is interference between macro- and femto-cells. Using Orthogonal Frequency-Division Multiple Access (OFDMA) to create multiple frequency orthogonal sub-channels, this interference can be completely ... More
Exploiting Capture Effect in Frameless ALOHA for Massive Wireless Random AccessJan 08 2014The analogies between successive interference cancellation (SIC) in slotted ALOHA framework and iterative belief-propagation erasure-decoding, established recently, enabled the application of the erasure-coding theory and tools to design random access ... More
Buffer-Aided Relaying with Adaptive Link SelectionFeb 24 2012Oct 13 2012In this paper, we consider a simple network consisting of a source, a half-duplex decode-and-forward relay, and a destination. We propose a new relaying protocol employing adaptive link selection, i.e., in any given time slot, based on the channel state ... More
Ultra-Reliable Low Latency Communication (URLLC) using Interface DiversityNov 21 2017An important ingredient of the future 5G systems will be Ultra-Reliable Low-Latency Communication (URLLC). A way to offer URLLC without intervention in the baseband/PHY layer design is to use interface diversity and integrate multiple communication interfaces, ... More
Coded Splitting Tree ProtocolsJan 30 2013This paper presents a novel approach to multiple access control called coded splitting tree protocol. The approach builds on the known tree splitting protocols, code structure and successive interference cancellation (SIC). Several instances of the tree ... More
On the Role of Feedback in LT CodesDec 13 2010This paper concerns application of feedback in LT codes. The considered type of feedback is acknowledgments, where information on which symbols have been decoded is given to the transmitter. We identify an important adaptive mechanism in standard LT codes, ... More
Variable-Length Coding with Stop-Feedback for the Common-Message Broadcast Channel in the Nonasymptotic RegimeJul 12 2016We investigate the maximum coding rate for a given average blocklength and error probability over a K-user discrete memoryless broadcast channel for the scenario where a common message is transmitted using variable-length stop-feedback codes. For the ... More
Massive MIMO for Ultra-reliable Communications with Constellations for Dual Coherent-noncoherent DetectionFeb 28 2018Mar 21 2018The stringent requirements of ultra-reliable low-latency communications (URLLC) require rethinking of the physical layer transmission techniques. Massive antenna arrays are seen as an enabler of the emerging $5^\text{th}$ generation systems, due to increases ... More
Common-Message Broadcast Channels with Feedback in the Nonasymptotic Regime: Full FeedbackJun 23 2017Aug 30 2018We investigate the maximum coding rate achievable on a two-user broadcast channel for the case where a common message is transmitted with feedback using either fixed-blocklength codes or variable-length codes. For the fixed-blocklength-code setup, we ... More
Random Access for Massive MIMO Systems with Intra-Cell Pilot ContaminationSep 28 2015Jun 07 2016Massive MIMO systems, where the base stations are equipped with hundreds of antenna elements, are an attractive way to attain unprecedented spectral efficiency in future wireless networks. In the "classical" massive MIMO setting, the terminals are assumed ... More
Blahut-Arimoto Algorithm and Code Design for Action-Dependent Source Coding ProblemsJan 25 2013The source coding problem with action-dependent side information at the decoder has recently been introduced to model data acquisition in resource-constrained systems. In this paper, an efficient algorithm for numerical computation of the rate-distortion-cost ... More
Wirelessly Powered Communication Networks with Short PacketsOct 24 2016Nov 01 2016Wirelessly powered communications will entail short packets due to naturally small payloads, low-latency requirements and/or insufficient energy resources to support longer transmissions. In this paper, a wirelessly powered communication system is investigated ... More
Design and Performance Analysis of Non-Coherent Detection Systems with Massive Receiver ArraysJun 20 2016Harvesting the gain of a large number of antennas in a mmWave band has mainly been relying on the costly operation of channel state information (CSI) acquisition and cumbersome phase shifters. Recent works have started to investigate the possibility to ... More
Massive Random Access with Common Alarm MessagesJan 18 2019The established view on massive IoT access is that the IoT devices are activated randomly and independently. This is a basic premise also in the recent information-theoretic treatment of massive access by Polyanskiy. In a number of practical scenarios, ... More
Massive M2M Access with Reliability Guarantees in LTE SystemsFeb 10 2015Machine-to-Machine (M2M) communications are one of the major drivers of the cellular network evolution towards 5G systems. One of the key challenges is on how to provide reliability guarantees to each accessing device in a situation in which there is ... More
Aggregation and Trunking of M2M Traffic via D2D ConnectionsFeb 05 2015Machine-to-Machine (M2M) communications is one of the key enablers of the Internet of Things (IoT). Billions of devices are expected to be deployed in the next future for novel M2M applications demanding ubiquitous access and global connectivity. In order ... More
Joint Estimation and Contention-Resolution Protocol for Wireless Random AccessOct 02 2012We propose a contention-based random-access protocol, designed for wireless networks where the number of users is not a priori known. The protocol operates in rounds divided into equal-duration slots, performing at the same time estimation of the number ... More
Random Access Schemes in Wireless Systems With Correlated User ActivityMar 09 2018Traditional random access schemes are designed based on the aggregate process of user activation, which is created on the basis of independent activations of the users. However, in Machine-Type Communications (MTC), some users are likely to exhibit a ... More
Minimizing Data Distortion of Periodically Reporting IoT Devices with Energy HarvestingJun 29 2017Energy harvesting is a promising technology for the Internet of Things (IoT) towards the goal of self-sustainability of the involved devices. However, the intermittent and unreliable nature of the harvested energy demands an intelligent management of ... More
Joint Retransmission, Compression and Channel Coding for Data Fidelity under Energy ConstraintsJun 28 2017We consider a monitoring application where sensors periodically report data to a common receiver in a time division multiplex fashion. The sensors are constrained by the limited and unpredictable energy availability provided by Energy Harvesting (EH), ... More
Analysis of the Communication Traffic for Blockchain Synchronization of IoT DevicesNov 01 2017Feb 12 2018Blockchain is a technology uniquely suited to support massive number of transactions and smart contracts within the Internet of Things (IoT) ecosystem, thanks to the decentralized accounting mechanism. In a blockchain network, the states of the accounts ... More
Wireless Channel Modeling Perspectives for Ultra-Reliable Low Latency CommunicationsMay 04 2017Jan 12 2018Ultra-Reliable Low Latency Communication (URLLC) is one of the distinctive features of the upcoming 5G wireless communication, going down to packet error rates (PER) of $10^{-9}$. In this paper we discuss the statistical properties of the wireless channel ... More
Anti-Jamming Strategy for Distributed Microgrid Control based on Power Talk CommunicationDec 21 2016Dec 22 2016In standard implementations of distributed secondary control for DC MicroGrids (MGs), the exchange of local measurements among neighboring control agents is enabled via off-the-shelf wireless solutions, such as IEEE 802.11. However, Denial of Service ... More
Power Talk in DC Micro Grids: Constellation Design and Error Probability PerformanceJul 09 2015Power talk is a novel concept for communication among units in a Micro Grid (MG), where information is sent by using power electronics as modems and the common bus of the MG as a communication medium. The technique is implemented by modifying the droop ... More
Massive MIMO for Crowd Scenarios: A Solution Based on Random AccessMay 21 2015This paper presents a new approach to intra-cell pilot contamination in crowded massive MIMO scenarios. The approach relies on two essential properties of a massive MIMO system, namely near-orthogonality between user channels and near-stability of channel ... More
Non-Orthogonal Multiplexing of Ultra-Reliable and Broadband Services in Fog-Radio ArchitecturesSep 05 2018Dec 21 2018The fifth generation (5G) of cellular systems is introducing Ultra-Reliable Low-Latency Communications (URLLC) services alongside more conventional enhanced Mobile BroadBand (eMBB) traffic. Furthermore, the 5G cellular architecture is evolving from a ... More
Massive Random Access with Common Alarm MessagesJan 18 2019Apr 26 2019The established view on massive IoT access is that the IoT devices are activated randomly and independently. This is a basic premise also in the recent information-theoretic treatment of massive access by Polyanskiy. In a number of practical scenarios, ... More
Delay and Communication Tradeoffs for Blockchain Systems with Lightweight IoT ClientsJul 19 2018Oct 17 2018The emerging blockchain protocols provide a decentralized architecture that is suitable of supporting Internet of Things (IoT) interactions. However, keeping a local copy of the blockchain ledger is infeasible for low-power and memory-constrained devices. ... More
Joint Configuration of Transmission Direction and Altitude in UAV-based Two-Way CommunicationMay 21 2018When considering unidirectional communication for unmanned aerial vehicles (UAVs) as flying Base Stations (BSs), either uplink or downlink, the system is limited through the co-channel interference that takes place over line-of-sight (LoS) links. This ... More
Distributed Proportional-Fairness Control in MicroGrids via Blockchain Smart ContractsMay 03 2017May 16 2017Residential microgrids (MGs) may host a large number of Distributed Energy Resources (DERs). The strategy that maximizes the revenue for each individual DER is the one in which the DER operates at capacity, injecting all available power into the grid. ... More
Grant-Free Radio Access for Short-Packet Communications over 5G NetworksSep 07 2017Radio access management plays a vital role in delay and energy consumption of connected devices. The radio access in existing cellular networks is unable to efficiently support massive connectivity, due to its signaling overhead. In this paper, we investigate ... More
Massive Machine-Type Communication (mMTC) Access with Integrated AuthenticationOct 31 2016Mar 15 2017We present a connection establishment protocol with integrated authentication, suited for Massive Machine-Type Communications (mMTC). The protocol is contention-based and its main feature is that a device contends with a unique signature that also enables ... More