| 1. |
- Akbar, Noman, et al.
(författare)
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Downlink Power Control in Massive MIMO Networks with Distributed Antenna Arrays
- 2018
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Ingår i: 2018 IEEE INTERNATIONAL CONFERENCE ON COMMUNICATIONS (ICC). - : IEEE. - 9781538631805 - 9781538631812
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Konferensbidrag (refereegranskat)abstract
- In this paper, we investigate downlink power control in massive multiple-input multiple-output (MIMO) networks with distributed antenna arrays. The base station (BS) in each cell consists of multiple antenna arrays, which are deployed in arbitrary locations within the cell. Due to the spatial separation between antenna arrays, the large-scale propagation effect is different from a user to different antenna arrays in a cell, which makes power control a challenging problem as compared to conventional massive MIMO. We assume that the BS in each cell obtains the channel estimates via uplink pilots. Based on the channel estimates, the BSs perform maximum ratio transmission for the downlink. We then derive a closed-form spectral efficiency (SE) expression, where the channels are subject to correlated fading. Utilizing the derived expression, we propose a max-min power control algorithm to ensure that each user in the network receives a uniform quality of service. Numerical results demonstrate that, for the network considered in this work, optimizing for max-min SE through the max-min power control improves the sum SE of the network as compared to the equal power allocation.
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| 2. |
- Dimitriou, Ioannis, et al.
(författare)
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Performance Analysis of an Adaptive Queue-Aware Random Access Scheme with Random Traffic
- 2018
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Ingår i: 2018 IEEE International Conference on Communications (ICC) Proceedings Kansas City, MO, USA 20–24 May 2018. - : IEEE Communications Society. - 9781538631805 - 9781538631812 ; , s. 1-6
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Konferensbidrag (refereegranskat)abstract
- In this work, we consider an adaptive two-user random access scheme with multipacket reception (MPR) ca- pabilities. A user adapts its transmission characteristics based on the status of the other user. The users have external random traffic stored in their queues. We derive the stable throughput region of the system and the convexity conditions of this region. We derive analytically the queueing delay by formulating and solving a Riemann-Hilbert boundary value problem. Finally, we evaluate numerically the presented theoretical results.
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| 3. |
- Farag, Hossam, et al.
(författare)
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PR-CCA MAC : A Prioritized Random CCA MAC Protocol for Mission-Critical IoT Applications
- 2018
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Ingår i: 2018 IEEE International Conference on Communications (ICC). - : IEEE. - 9781538631805 - 9781538631812
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Konferensbidrag (refereegranskat)abstract
- A fundamental challenge in Mission-Critical Internetof Things (MC-IoT) is to provide reliable and timely deliveryof the unpredictable critical traffic. In this paper, we propose an efficient prioritized Medium Access Control (MAC) protocol for Wireless Sensor Networks (WSNs) in MC-IoT control applications. The proposed protocol utilizes a random Clear Channel Assessment (CCA)-based channel access mechanism to handlethe simultaneous transmissions of critical data and to reduce thecollision probability between the contending nodes, which in turn decreases the transmission latency. We develop a Discrete-Time Markov Chain (DTMC) model to evaluate the performance of the proposed protocol analytically in terms of the expected delay and throughput. The obtained results show that the proposed protocolcan enhance the performance of the WirelessHART standard by 80% and 190% in terms of latency and throughput, respectively along with better transmission reliability.
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| 4. |
- Guntupalli, Lakshmikanth, et al.
(författare)
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Priority-Oriented Packet Transmissions in Internet of Things : Modeling and Delay Analysis
- 2018
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Ingår i: 2018 IEEE International Conference on Communications (ICC). - : IEEE. - 9781538631805 - 9781538631812
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Konferensbidrag (refereegranskat)abstract
- Priority-oriented packet transmission (PPT) has been a promising solution for transmitting time-critical packets in timely manner during emergency scenarios in Internet ofThings (IoT). In this paper, we develop two associated discrete time Markov chain (DTMC) models to analyze performance of the PPT in an IoT network. Using the proposed DTMC models, we investigate the effect of traffic prioritization interms of average packet delay for a synchronous medium access control (MAC) protocol. Furthermore, the results obtained from analytical models are validated via discrete-event simulations. Numerical results prove the accuracy of the models and reveal the behavior of priority based packet transmissions.
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| 5. |
- Mishra, Deepak, 1990-, et al.
(författare)
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Harvested power fairness optimization in MISO SWIPT multicasting IoT with individual constraints
- 2018
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Ingår i: 2018 IEEE International Conference on Communications (ICC). - : Institute of Electrical and Electronics Engineers (IEEE). - 9781538631805 - 9781538631812 ; , s. 1-6
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Konferensbidrag (refereegranskat)abstract
- In this paper, we consider a Multiple Input Single Output (MISO) multicasting Internet of Things (IoT) system comprising of a multiantenna Transmitter (TX) that simultaneously transfers information and power to low power and data hungry IoT devices. Each IoT device is assumed to be equipped with Power Splitting (PS) hardware that enables Energy Harvesting (EH) and imposes an individual Quality of Service (QoS) constraint to the downlink communication. We study the joint design of TX precoding and IoT PS ratios for the considered MISO Simultaneous Wireless Information and Power Transfer (SWIPT) multicasting IoT with the objective of maximizing the minimum harvested energy among IoT, while satisfying their individual QoS requirements. In our novel EH fairness maximization formulation, we adopt a generic Radio Frequency (RF) EH model capturing practical rectification operation, and resulting in a nonconvex optimization problem. For this problem, we first present an equivalent Semi- Definite Relaxation (SDR) for the considered design problem and prove that it possesses unique global optimality. Then, capitalizing on our derived tight upper and lower bounds on the optimal solution, we present an efficient algorithmic implementation for the jointly optimal TX precoding and IoT PS ratio parameters. Insights on the optimal TX precoding structure are also presented. Representative numerical results including comparisons with benchmark schemes corroborate the usefulness of the proposed design and provide useful insights on the interplay of critical system parameters on the optimized power vs achievable rate trade off.
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| 6. |
- You, Lei, et al.
(författare)
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Efficient Minimum-Energy Scheduling with Machine-Learning Based Predictions for Multiuser MISO Systems
- 2018
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Ingår i: 2018 IEEE International Conference on Communications (ICC). - : IEEE. - 9781538631805 - 9781538631812 ; , s. 1-6
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Konferensbidrag (refereegranskat)abstract
- We address an energy-efficient scheduling problem for practical multiple-input single-output (MISO) systems with stringent execution-time requirements. Optimal user-group scheduling is adopted to enable timely and energy-efficient data transmission, such that all the users' demand can be delivered within a limited time. The high computational complexity in optimal iterative algorithms limits their applications in real-time network operations. In this paper, we rethink the conventional optimization algorithms, and embed machine-learning based predictions in the optimization process, aiming at improving the computational efficiency and meeting the stringent execution-time limits in practice, while retaining competitive energy-saving performance for the MISO system. Numerical results demonstrate that the proposed method, i.e., optimization with machine- learning predictions (OMLP), is able to provide a time-efficient and high-quality solution for the considered scheduling problem. Towards online scheduling in real-time communications, OMLP is of high computational efficiency compared to conventional optimal iterative algorithms. OMLP guarantees the optimality as long as the machine- learning based predictions are accurate.
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| 7. |
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| 8. |
- Ibarra, Diego, et al.
(författare)
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Software-Based Implementation of LTE/Wi-Fi Aggregation and Its Impact on Higher Layer Protocols
- 2018
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Ingår i: IEEE International Conference on Communications ICC2018. - 9781538631805
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Konferensbidrag (refereegranskat)abstract
- Due to the fast growing of data consumed in mobile devices through cellular networks, solutions that provide higher data rates are an important target for the mobile networking community. One such solution is the aggregation of mobile technologies (most commonly LTE) with wireless LAN solutions (most commonly Wi-Fi). Seeing its potential impact, 3GPP has devised the LTE/Wi-Fi Aggregation (LWA) specification, which defines a tight coupling between eNBs and Wi-Fi Access Points (APs). In this paper, we implement and evaluate an LWA solution, and compare its performance to the one for full offloading (only Wi-Fi) and no offloading (only LTE) through physical experimentation. The developed prototype LWA solution is based on open source and commodity hardware, which promises a low-cost and easily implementable LWA solution. Aggregation and offloading process are managed by the eNB, therefore, the core network remains intact without any modification. Physical experiments are done to detail the network performances for all these three policies for TCP and UDP traffic and both for uplink and downlink connections. In TCP transmissions with LWA policy, the different delays between Wi-Fi and LTE links causes the performance degradation because of the out-of-order arrivals of the segments. For this, we evaluate a solution where an artificial delay is added to reduce the number of out-of-order packets.
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| 9. |
- Liu, S., et al.
(författare)
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Control under Intermittent Network Partitions
- 2018
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Ingår i: 2018 IEEE International Conference on Communications (ICC). - : Institute of Electrical and Electronics Engineers (IEEE). - 9781538631805
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Konferensbidrag (refereegranskat)abstract
- We propose a novel distributed leader election algorithm to deal with the controller and control service availability issues in programmable networks, such as Software Defined Networks (SDN) or programmable Radio Access Network (RAN). Our approach can deal with a wide range of network failures, especially intermittent network partitions, where splitting and merging of a network repeatedly occur. In contrast to traditional leader election algorithms that mainly focus on the (eventual) consensus on one leader, the proposed algorithm aims at optimizing control service availability, stability and reducing the controller state synchronization effort during intermittent network partitioning situations. To this end, we design a new framework that enables dynamic leader election based on real-time estimates acquired from statistical monitoring. With this framework, the proposed leader election algorithm has the capability of being flexibly configured to achieve different optimization objectives, while adapting to various failure patterns. Compared with two existing algorithms, our approach can significantly reduce the synchronization overhead (up to 12x) due to controller state updates, and maintain up to twice more nodes under a controller.
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| 10. |
- Masoudi, Meysam, et al.
(författare)
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Grant-Free Radio Access IoT Networks : Scalability Analysis in Coexistence Scenarios
- 2018
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Ingår i: IEEE International Conference on Communications. - : Institute of Electrical and Electronics Engineers Inc.. - 9781538631805
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Konferensbidrag (refereegranskat)abstract
- IoT networks with grant-free radio access, like SigFox and LoRa, offer low-cost durable communications over unlicensed band. These networks are becoming more and more popular due to the ever-increasing need for ultra durable, in terms of battery lifetime, IoT networks. Most studies evaluate the system performance assuming single radio access technology deployment. In this paper, we study the impact of coexisting competing radio access technologies on the system performance. Considering K technologies, defined by time and frequency activity factors, bandwidth, and power, which share a set of radio resources, we derive closed-form expressions for the successful transmission probability, expected battery lifetime, and experienced delay as a function of distance to the serving access point. Our analytical model, which is validated by simulation results, provides a tool to evaluate the coexistence scenarios and analyze how introduction of a new coexisting technology may degrade the system performance in terms of success probability and battery lifetime. We further investigate solutions in which this destructive effect could be compensated, e.g., by densifying the network to a certain extent and utilizing joint reception.
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