Search

We propose partial packet duplication; when cellular dual connectivity is available we propose to duplicate only during some portion of the time as needed. This satisfies reliability constraints defined as (1) the probability of fades staying shorter than a certain duration and (2) the probability of non-fades (i.e., time back above the SINR threshold) lasting longer than a certain duration. Fade durations and non-fade durations have been estimated in the literature to fit exponential distributions. We also choose exponential random variables to control duplication processes, which allows Markov chain modeling of the entire process. Using matrix exponential distribution formulations of the Markov chain in the context of partial packet duplication, we fully describe the partial packet duplication behavior, examine asymptotic performance, and define ranges of duplication parameters that meet both fade and non-fade duration constraints. Then we choose the best parameters that minimize resources used on the secondary link for packet duplication. [ABSTRACT FROM AUTHOR]

In this paper, we explore the effect of dual connectivity (DC) on delay-aware resource control with statistical Quality of Service (QoS) provisioning in heterogeneous aeronautical networks. Firstly, the Software Defined Networking (SDN) controller is introduced to support the DC for aircraft by centralized management of different base stations. In light of the delay analysis of user traffic, the delay-aware resource control of SDN controller is established as a multi-objective stochastic optimization problem to guarantee the statistical QoS provisioning. Secondly, the multi-objective stochastic optimization problem is transformed into a weighted single-objective optimization and relaxed by the Lagrangian relaxation. Then, the Lyapunov optimization theory is utilized to solve the relaxed stochastic optimization for optimal resource control. Finally, the performance of resource control under DC mode is verified in two aeronautical scenarios. [ABSTRACT FROM AUTHOR]

The rapid increase of wireless applications and services coupled with the arrival of 5G and Internet of Things will not only exacerbate demand for further capacity at the downlink (DL) but also crucially at the uplink (UL). One of the most potential enablers to simultaneously optimize both links is the DL/UL decoupling (DUDe) technique which does so by exploiting the possibility of associating each user to a different base station (BS) in each link direction. Moreover, the increasing desire to incorporate millimeter-wave (mmWave) communications in future networks further enriches the possibilities to achieve higher capacities. To this end and in contrast to existing works which use dual association based on minimum path-loss (Min-PL), this paper investigates the merits of adopting capacity-based multi-association in ultra-high frequency (UHF) and mmWave hybrid networks, where mobile users may simultaneously connect to multiple UHF small cells (SCells), millimeter-wave SCells and/or UHF macro cells (MCells). It will be shown that, our joint association and resource management approach can provide higher data rates and energy efficiency than many benchmark techniques. To achieve an insight into the performance of the proposed design, the results present a comprehensive comparison based on single and multi-connectivity as well as coupled and decoupled association for a variety of important metrics. [ABSTRACT FROM AUTHOR]

In future 5G user-centric ultra-dense networks (UUDN), demands of high data rate and high spectrum efficiency are effectively met by dual connectivity (DC) technology. However, due to huge increase of base stations (BSs) and mobile users (MUs), it becomes difficult for BSs to quickly and precisely select the codeword and provide DC to MUs. Hence, different from some traditional methods, this correspondence paper aims to improve the network performance using the method of machine learning. First, we model the random distribution of BSs by homogeneous Poisson point processes, where each MU is served by millimeter-wave channel. Second, the probabilities that macro cell BS or small cell BS serves the MU are further derived to get the average sum rate (ASR) in UUDN. Third, inspired by ML, we utilize an iterative support vector machine (SVM) classifier to select the codewords of BSs, with sequential minimal optimization (SMO) algorithm used for training all link samples in UUDN. Then, an iterative SVM-SMO classification algorithm is proposed to achieve a highly efficient performance of DC, where the convergence and complexity are also discussed. The sample training and simulation at last are evaluated by Google TensorFlow. The simulation verified that our proposed algorithm gets a higher ASR than the traditional channel estimation based algorithm. In addition, the results also show a lower computational complexity can be achieved by the proposed algorithm as well. [ABSTRACT FROM AUTHOR]

This paper presents a video quality-aware traffic offloading system that provides seamless video streaming services to users by offloading part of the macrobase station traffic into small cells. The proposed system achieves a good balance between fairness and social welfare in terms of the video quality by allocating the radio resource of the macrobase station. The data flow is split into two parts toward the macrobase station and small cell AP, and the users simultaneously receive their data from both. In the proposed system, fountain code is employed to achieve dual connectivity enhancement by overcoming frequent packet loss in error-prone mobile networks and practical issues in the dual connectivity architecture. Furthermore, software-defined networking (SDN) technology is adopted not only to quickly react to time-varying network status but also to control network resources efficiently. The proposed resource allocation process is designed to require a low running time complexity. The proposed system is implemented using C/C++, Java, and a well-known open source, ONOS. The experimental results verify that the proposed system can achieve much better performance than other offloading algorithms. [ABSTRACT FROM AUTHOR]

The shared resource access wireless communication system is regarded as an efficient paradigm that allows the mobile network operators to have extended coverage and satisfy their subscribers’ high capacity demands while keeping the capital and operational expenditure in check. On the other hand, dual connectivity (DC), a small cell enhancement feature, allows the subscribers to have two simultaneous connections increasing throughput and enhancing mobility robustness. The coordinated multipoint (CoMP) transmission/reception and user-centric virtual cell (VC) improve the signal quality and performance. For all of these mechanisms, the user needs to be under the coverage of multiple base stations (BSs) concurrently. Because of the random nature of the wireless links and distribution of BSs in a network, the practicability/operability of DC and CoMP/VC for a typical user under such random operating conditions (both topological and wireless link randomness) needs to be adequately evaluated. In this paper, we take an extensive look at this problem exploiting tools from Poisson point process theory and stochastic geometry and derive easy-to-evaluate tractable integral expressions for essential performance metrics such as DC and CoMP/VC coverage probability of a typical user in downlink cellular. Unlike most of the existing works, we consider a signal propagation loss model, where the selection of the strongest (not necessarily the closest) BS that serves the typical user is perturbed by arbitrary shadowing, not by fading, i.e., we consider a fading-averaged signal propagation loss process. We derive the coverage probability as a function of various system parameters such as BS density, fading parameters, the cardinality of the coordination set for CoMP/VC, etc. We verify the analytical analysis with simulation results [ABSTRACT FROM AUTHOR]

A control/user (C/U) plane-split network, where macro- and microevolved Node Bs (eNBs) are responsible for C/U-planes, respectively, is a potential 5G solution to address the problems experienced by high-speed railway communication systems such as frequent handovers (HOs), low system capacity, and low data rate. The C-plane transition occurs during an intermacro eNB HO to reduce the frequency of HOs. However, the intermacro-eNB HO in a C/U-plane-split network is prone to handover failures (HOFs) and long service interruption time similar to the traditional long-term evolution-advanced (LTE-A) HO without improvements because it is similar to an LTE-A HO between macro-eNBs from the perspective of C-plane transition. In this paper, we realize a C/U-plane-split network using the LTE-A dual-connectivity (DC) technique and propose a dc-based prevenient HO (PHO) scheme to improve the robustness of the intermacro-eNB HO. The proposed scheme specifically is an a priori method and uses the transmit diversity based on the dc technique to reduce the risk of HOFs and the long service interruption time. Further, we first develop the analytical expressions for HO performance for PHO and LTE-A HO, where HOFs are aligned with the LTE-A specifications such that they are defined as the association between the radio link monitor and HO processes. The analytical results are verified against simulation results. Through simulations, we compare PHO with LTE-A HO and the representative schemes of the previous literature in a variety of mobility performance metrics (such as the averages of the successful HO rate, the HOF rate, the radio link failure rate, the ping-pong rate, and the service interrupt time). The results confirm that the proposed scheme achieves superior performance in the key metrics of the successful HO rate and service interrupt time. [ABSTRACT FROM PUBLISHER]