Abstract:Wireless big data describes a wide range of massive data that is generated,collected and stored in wireless networks by wireless devices and users.While these data share some common properties with traditional big data,they have their own unique characteristics and provide numerous advantages for academic research and practical applications.This article reviews the recent advances and trends in the field of wireless big data.Due to space constraints,this survey is not intended to cover all aspects in this field,but to focus on the data aided transmission,data driven network optimization and novel applications.It is expected that the survey will help the readers to understand this exciting and emerging research field better.Moreover,open issues and promising future directions are also identified.
The 5G (fifth generation) mobile communications aim to support a large versatile type of services with different and often diverging requirements, which has posed significant challenges on the design of 5G systems.Modulation and waveforms are one of the key physical layer componentsthat determine the system throughput, reliability, and complexity, therefore their design is critical in meeting the variety requirements of 5G services.A comprehensive overview was presented on the modulation and waveforms that have been considered for their potential application to 5G in the literature, identifying their design requirements, and discussing their advantages to meet such requirements.Additional considerations that extend our view to higher layer aspects and air interface harmonization are provided as the final remarks.As a result of this article, it is hopeful to draw greater attentions from the readers on this important topic, and trigger further studies on the promising modulation and waveform candidates.
Cyber-physical systems are being confronted with an ever-increasing number of security threats from the complicated interactions and fusions between cyberspace and physical space.Integrating security-related activities into the early phases of the development life cycle is a monolithic and cost-effective solution for the development of security-critical cyber-physical systems.These activities often incorporate security mechanisms from different realms.We present a fine-grained design flow paradigm for security-critical and software-intensive cyber-physical systems.We provide a comprehensive survey on the domain-specific architectures, countermeasure techniques and security standards involved in the development life cycle of security-critical cyber-physical systems, and adapt these elements to the newly designed flow paradigm.Finally, we provide prospectives and future directions for improving the usability and security level of this design flow paradigm.
Abstract:In HetNets (Heterogeneous Networks),each network is allocated with fixed spectrum resource and provides service to its assigned users using specific RAT (Radio Access Technology).Due to the high dynamics of load distribution among different networks,simply optimizing the performance of individual network can hardly meet the demands from the dramatically increasing access devices,the consequent upsurge of data traffic,and dynamic user QoE(Quality-of-Experience).The deployment of smart networks,which are supported by SRA (Smart Resource Allocation)among different networks and CUA (Cognitive User Access) among different users,is deemed a promising solution to these challenges.In this paper,we propose a framework to transform HetNets to smart networks by leveraging WBD(Wireless Big Data),CR(Cognitive Radio) and NFV (Network Function Virtualization) techniques.CR and NFV support resource slicing in spectrum,physical layers,and network layers,while WBD is used to design intelligent mechanisms for resource mapping and traffic prediction through powerful AI (Artificial Intelligence) methods.We analyze the characteristics of WBD and review possible AI methods to be utilized in smart networks.In particular,the potential of WBD is revealed through high level view on SRA,which intelligently maps radio and network resources to each network for meeting the dynamic traffic demand,as well as CUA,which allows mobile users to access the best available network with manageable cost,yet achieving target QoS(Quality-of-Service)or QoE.
Applications of VANETs (Vehicular Ad hoc Networks) have their own requirements and challenges in wireless communication technology.Although regarded as the first standard for VANETs,IEEE 802.11p is still in the field-trial stage.Recently,LTE V2X(Long-Term Evolution Vehicular to X)appeared as a systematic V2X solution based on TD-LTE(Time Division Long-Term Evolution)4G.It is regarded as the most powerful competitor to 802.11p.We conduct link level simulations of LTE V2X and DSRC (Dedicated Short-Range Communication)for several different types of scenarios.Simulation results show that LTE V2X can achieve the same BLER(Block Error Ratio)with a lower SNR(Signal Noise Ratio)than DSRC.A more reliable link can be guaranteed by LTE V2X,which can achieve the same BLER with lower receiving power than DSRC.The coverage area of LTE V2X is larger than that of DSRC.
In recent years,IoV (Internet of Vehicles) has become one of the most active research fields in network and intelligent transportation system.As an open converged network,IoV plays an important role in solving various driving and traffic problems by advanced information and communications technology.We review the existing notions of IoV from different perspectives.Then,we provide our notion from a network point of view and propose a novel IoV architecture with four layers.Particularly,a novel layer named coordinative computing control layer is separated from the application layer.The novel layer is used for solving the coordinative computing and control problems for human-vehicle-environment.After summarizing the key technologies in IoV architecture,we construct a VV (Virtual Vehicle),which is an integrated image of driver and vehicle in networks.VVs can interact with each other in cyber space by providing traffic service and sharing sensing data coordinately,which can solve the communication bottleneck in physical space.Finally,an extended IoV architecture based on VVs is proposed.
Cloud computing facilitates convenient and on-demand network access to a centralized pool of resources.Currently, many users prefer to outsource data to the cloud in order to mitigate the burden of local storage.However, storing sensitive data on remote servers poses privacy challenges and is currently a source of concern.SE (Searchable Encryption) is a positive way to protect users sensitive data, while preserving search ability on the server side.SE allows the server to search encrypted data without leaking information in plaintext data.The two main branches of SE are SSE (Searchable Symmetric Encryption) and PEKS (Public key Encryption with Keyword Search).SSE allows only private key holders to produce ciphertexts and to create trapdoors for search, whereas PEKS enables a number of users who know the public key to produce ciphertexts but allows only the private key holder to create trapdoors.This article surveys the two main techniques of SE: SSE and PEKS.Different SE schemes are categorized and compared in terms of functionality, efficiency, and security.Moreover, we point out some valuable directions for future work on SE schemes.
Chandran, et al.introduce the direction of position based cryptography at CRYPTO 2009.In position based cryptography, the position of a party is used to be its unique “credential” in order to realize the cryptographic tasks, such as position based encryption, position based signature, position based key exchange and so on.Position based key exchange, as a basic primitive in position based cryptography, can be used to establish a shared key based on the position of the participant.To begin with, this paper presents the notions of the prover-to-verifier mode and the prover-to-prover mode for position based key exchange.In the prover-to-verifier mode, a secret key can be shared between a prover and the verifiers according to the position of the prover.While in the prover-to-prover mode, two provers located at the valid positions can negotiate a shared key with the help of the verifiers and any other party whose position is illegal cannot obtain the shared key.At the same time, this paper formalizes two security definitions against colluding adversaries: position based prover-to-verifier key exchange and position based prover-to-prover key exchange.Then, this paper introduces the bounded retrieval model and the implementations of position based key exchange in two modes based on the bounded retrieval model.Finally, this paper discusses the position based key exchange protocols in two modes from both security and performance perspectives.
In vehicular networks,the exchange of beacons among neighboring vehicles is a promising solution to guarantee a vehicle’s safety.However,frequent beaconing under high vehicle density conditions will cause beacon collisions,which are harmful to a vehicle’s driving safety and the location tracking accuracy.We propose an ABIwRC (Adaptive Beaconing Interval with Resource Coordination) method for a highway scenario.Each vehicle broadcasts beacon interval requests,including the intervals needed for both the vehicle’s driving safety and location tracking accuracy.The RSU(Road Side Unit) allocates resources for a vehicle’s beaconing according to the requests from all vehicles and the interference relationship between the vehicles in adjacent RSUs.We formulate a resource allocation problem for maximizing the sum utility,which measures the satisfaction of vehicles’requests.We then transform the optimization problem into a maximum weighted independent set problem,and propose an algorithm to solve this efficiently.Simulation results show that the proposed method outperforms the benchmark in terms of beacon reception ratio,vehicle driving safety,and location tracking accuracy.
IoV (Internet of Vehicles) is a promising paradigm to the future of automobiles, which will undoubtedly boost the automobile market as well as accelerate innovation in Internet services and applications.The concept of SD-IoV (Software Defined IoV) is presented, which is capable of improving resource utilization, service quality, and network optimization in the harsh vehicular network environments.First, A generalized SD-IoV architecture as an intuitive big picture is presented.Then, the major functions realized by SD-IoV are elabrated on to illustrate how the current challenges are resolved.As the key enablers of SD-IoV, three possible implementation methods of the wireless control path are described and compared.Finally, the challenges and existing solutions of SD-IoV are disuessed and open issues are pointed out so as to shed light on future research.
In the age of information explosion,big data has brought challenges but also great opportunities that support a wide range of applications for people in all walks of life.Faced with the continuous and intense competition from OTT service providers,traditional telecommunications service providers have been forced to undergo enterprise transformation.Fortunately,these providers have natural and unique advantages in terms of both data sources and data scale,all of which give them a competitive advantage.Multiple foreign mainstream telecom operators have already applied big data for their own growth,from internal business to external applications.Armed with big data,domestic telecom companies are also innovating business models.This paper will introduce three aspects of big data in the telecommunications industry.First,the unique characteristics and advantages of communications industry big data are discussed.Second,the development of the big data platform architecture is introduced in detail,which incorporates five crucial sub-systems.We highlight the data collection and data processing systems.Finally,three internal or external application areas based on big data analysis are discussed,namely basic business,network construction,and intelligent tracing.Our work sheds light on how to deal with big data for telecommunications enterprise development.
The widespread application of heterogeneous cloud computing has enabled enormous advances in the real-time performance of telehealth systems.A cloud-based telehealth system allows healthcare users to obtain medical data from various data sources supported by heterogeneous cloud providers.Employing data duplications in distributed cloud databases is an alternative approach for achieving data sharing among multiple data users.However, this approach results in additional storage space being used, even though reducing data duplications would lead to a decrease in data acquisitions and realtime performance.To address this issue, this paper focuses on developing a dynamic data deduplication method that uses an intelligent blocker to determine the working mode of data duplications for each data package in heterogeneous cloudbased telehealth systems.The proposed approach is named the SD2M (Smart Data Deduplication Model), in which the main algorithm applies dynamic programming to produce optimal solutions to minimizing the total cost of data usage.We implement experimental evaluations to examine the adaptability of the proposed approach.
Abstract: With the support of the national nature science foundation, the Academy of Space Electronic Information Technology is developing a novel compact spaceborne GNSS receiver, referred to as the HiSGR (High Sensitivity GNSS Receiver). This receiver can operate effectively in the full range of Earth orbiting missions, from LEO (Low Earth Orbit) to geostationary and beyond. Improved signal detection algorithms are used in the signal process section of the HiSGR and an inertial sensor is used for GNSS/INS ultra tight coupled design, which makes the acquisition process fast and provides improved tracking performance for weaker GPS signals in the presence of high dynamics. Extensive tests are performed using the HiSGR to demonstrate the good performance of some crucial specifications, by employing a real GNSS signal received in an open field and through hardware-in-the-loop simulation. Receiver performance is demonstrated for LEO and GEO scenarios. A ground vehicle running test is performed for demonstration of fast acquisition and reacquisition capabilities under conditions of signal loss. The HiSGR showed good performance and it was stable during the simulations and tests, which proved its capability for future space applications.
The wide spectrum and propagation characteristics over the air give mmWave communication unique advantages as well as design challenges for 5G applications.To increase the system speed,capacity,and coverage,there is a need for innovation in the RF system architecture,circuit,antenna,and package in terms of implementation opportunities and constraints.The discuss mmWave spectrum characteristics,circuits,RF system architecture,and their implementation issues are discussed.Moreover,the transmitter key components,i.e.,the receiver,antenna,and packaging are reviewed.
Recent rapid developments in 4G wireless communication have been motivated by breakthroughs in air interface technology,exemplified by the replacement of WCDMA (Wideband Code Division Multiple Access) with OFDM (Orthogonal Frequency-division Multiplexing).Although the protocol to adopt for 5G HF (High-Frequency) wireless communication—including such matters as waveform,network deployment,and frequency range—has been a controversial issue for a number of years,a common view is that there is a large gap between the rapidly increasing requirements pertaining to traffic capacity and the capabilities of current LTE (Long Term Evolution) networks in terms of spectral and power efficiency.A number of technical challenges need to be overcome in order to bridge this gap.In this paper,by briefly reviewing progress in HF technology,we summarize technical challenges ranging from propagation attenuation and the implementation of circuit devices,to signal processing and the Ka-band to offer feasible reflection on the forthcoming technological revolution.
A fully integrated 60-GHz transceiver for 802.11ad applications with superior performance in a 90-nm CMOS process versus prior arts is proposed and real based on a field-circuit co-design methodology.The reported transceiver monolithically integrates a receiver,transmitter,PLL(Phase-Locked Loop) synthesizer,and LO (Local Oscillator) path based on a sliding-IF architecture.The transceiver supports up to a 16QAM modulation scheme and a data rate of 6 Gbit/s per channel,with an EVM (Error Vector Magnitude) of lower than ?20 dB.The receiver path achieves a configurable conversion gain of 36~64 dB and a noise figure of 7.1 dB over 57~64 GHz,while consuming only 177 mW of power.The transmitter achieves a conversion gain of roughly 26 dB,with an output P1dBof 8 dBm and a saturated output power of over 10 dBm,consuming 252 mW of power from a 1.2-V supply.The LO path is composed of a 24-GHz PLL,doubler,and a divider chain,as well as an LO distribution network.In closed-loop operation mode,the PLL exhibits an integrated phase error of 3.3o rms (from 100 kHz to 100 MHz) over prescribed frequency bands,and a total power dissipation of only 26 mW.All measured results are rigorously loyal to the simulation.
Satellite networks have many advantages over traditional terrestrial networks.However, it is very difficult to design a satellite network with excellent performance.The paper briefly summarizes some existing satellite network routing technologies from the perspective of both single-layer and multilayer satellite constellations, and focuses on the main ideas, characteristics, and existing problems of these routing technologies.For single-layer satellite networks, two routing strategies are discussed, virtual node strategy and virtual topology strategy.Moreover, considering the deficiency of existing multilayer satellite network routing, we discuss the topic invulnerability.Finally, the challenges and problems faced by the satellite network are analyzed and the trend of future development is predicted.