| 1. |
- Aydin, Osman, et al.
(author)
-
EU FP7 INFSO-ICT-317669 METIS, D 4.1 Summary on preliminary trade-off investigations and first set of potential network-level solutions
- 2013
-
Reports (other academic/artistic)abstract
- METIS WP4 covers research activities in network-level aspects of the advancement of wireless network technologies towards the year 2020 and beyond. The aim is to develop novel network-level technology concepts to address the challenges foreseen in future scenarios with regard to interference, traffic and mobility management issues. Moreover, another task of this work package is to propose functional enablers which can support the above potential solutions.This document provides* a report of the ongoing progress in WP4 regarding the research topics agreed upon in IR 4.1,* a high level description of the proposed concepts and approaches adopted by different partners.More specifically, the document describes, first set of potential network-level solutions and presents some first research results in order to position them with regards to the state of the art approaches. It also gives an overview of research activities to be considered later in WP4.
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| 2. |
- Aydin, Osman, et al.
(author)
-
EU FP7 INFSO-ICT-317669 METIS, D4.2 Final report on trade-off investigations
- 2014
-
Reports (other academic/artistic)abstract
- Research activities in METIS WP4 include several aspects related to the network-level of future wireless communication networks. Thereby, a large variety of scenarios is considered and solutions are proposed to serve the needs envisioned for the year 2020 and beyond. This document provides vital findings about several trade-offs that need to be leveraged when designing future network-level solutions. In more detail, it elaborates on the following trade-offs:• Complexity vs. Performance improvement• Centralized vs. Decentralized• Long time-scale vs. Short time-scale• Information Interflow vs. Throughput/Mobility enhancement• Energy Efficiency vs. Network Coverage and CapacityOutlining the advantages and disadvantages in each trade-off, this document serves as a guideline for the application of different network-level solutions in different situations and therefore greatly assists in the design of future communication network architectures.
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| 3. |
- Carvalho, E. de, et al.
(author)
-
EU FP7 INFSO-ICT-317669 METIS, D3.1 Positioning of multi-node/multi-antenna technologies
- 2013
-
Reports (other academic/artistic)abstract
- This document describes the research activity in multi-node/multi-antenna technologies within METIS and positions it with respect to the state-of-the-art in the academic literature and in the standardization bodies. Based on the state-of-the-art and as well as on the METIS objectives,we set the research objectives and we group the different activities (or technology components) into research clusters with similar research objectives. The technologycomponents and the research objectives have been set to achieve an ambidextrous purpose. On one side we aim at providing the METIS system with those technological components that are a natural but non-trivial evolution of 4G. On the other side, we aim at seeking for disruptivetechnologies that could radically change 5G with respect to 4G. Moreover, we mapped the different technology components to METIS’ other activities and to the overall goals of theproject.
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| 4. |
- Fantini, R, et al.
(author)
-
EU FP7 INFSO-ICT-317669 METIS, D3.2 First performance results for multi-node/multi-antenna transmission technologies
- 2014
-
Reports (other academic/artistic)abstract
- This deliverable describes the current results of the multi-node/multi-antenna technologies investigated within METIS and analyses the interactions within and outside Work Package 3. Furthermore, it identifies the most promising technologies based on the current state of obtained results. This document provides a brief overview of the results in its first part. The second part, namely the Appendix, further details the results, describes the simulation alignment efforts conducted in the Work Package and the interaction of the Test Cases. The results described here show that the investigations conducted in Work Package 3 are maturing resulting in valuable innovative solutions for future 5G systems.
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| 5. |
- Lin, X., et al.
(author)
-
Positioning for the Internet of Things : A 3GPP Perspective
- 2017
-
In: IEEE Communications Magazine. - : Institute of Electrical and Electronics Engineers (IEEE). - 0163-6804 .- 1558-1896. ; 55:12, s. 179-185
-
Journal article (peer-reviewed)abstract
- Many use cases in the Internet of Things (IoT) will require or benefit from location information, making positioning a vital dimension of the IoT. The 3GPP has dedicated a significant effort during its Release 14 to enhance positioning support for its IoT technologies to further improve the 3GPPbased IoT eco-system. In this article, we identify the design challenges of positioning support in LTE-M and NB-IoT, and overview the 3GPP's work in enhancing the positioning support for LTE-M and NB-IoT. We focus on OTDOA, which is a downlink based positioning method. We provide an overview of the OTDOA architecture and protocols, summarize the designs of OTDOA positioning reference signals, and present simulation results to illustrate the positioning performance.
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| 6. |
- Papadogiannis, Agisilaos, 1982, et al.
(author)
-
Advanced Relaying Concepts for Future Wireless Networks
- 2012
-
In: Future Network and Mobile Summit (FUNEMS 2012), Berlin, Germany, July 2012. - 9781905824298
-
Conference paper (peer-reviewed)abstract
- Relaying is undoubtedly a key technology for future wireless networks as it can be applied to provide coverage extension and capacity increase in a cost-effective manner. This paper presents an outline of the major advanced relaying concepts that will be part of future systems from the viewpoint of the ARTIST4G European project. These concepts can be divided into three categories, those pertinent to type-1 relays, type-2 relays and moving relays. The characteristics of each of these concepts are presented and the challenges related to their implementation are discussed. Furthermore the paper proposes a set of solutions to address the discussed challenges. For type-1 relays, the paper presents solutions for the allocation of resources to the backhaul and the access links, the inter-relay interference mitigation, and the multi-hop transmission mode. For type-2 relays, our focus is on the design of distributed hybrid automatic repeat request (HARQ) protocols. More specifically we propose that the conventional HARQ schemes are adapted to exploit the potentially better channel conditions provided by the relays. Moreover distributed turbo coding solutions are introduced for increasing transmission reliability with the aid of relays. Finally, moving relays are presented as an efficient solution to the ever-growing demand for wireless broadband by users within public transportation vehicles. We show that moving relays can very effectively overcome vehicle penetration losses and boost the achievable capacities of the moving users. Overall, we conclude that the presented advanced relaying concepts are very promising and can significantly enhance the user experience in future wireless networks.
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| 7. |
- Papadogiannis, Agisilaos, 1982, et al.
(author)
-
The Potential of a Hybrid Fixed/User Relay Architecture -- A Performance Analysis
- 2012
-
In: IEEE Vehicular Technology Conference. - 1550-2252. - 9781467318808
-
Conference paper (peer-reviewed)abstract
- Future wireless systems are likely to comprise a dense grid of fixed relay nodes (FRNs) and contain a large number of user terminals (UTs) that can act as user relay nodes (URNs) under certain circumstances. In this paper we argue that significant gains can be attained if FRNs and URNs act together under the umbrella of a hybrid architecture. To this end, we derive closed-form expressions for the outage probability (OP) and an ergodic capacity upper bound of a dual-hop system as a function of the number of FRNs and URNs. For this analysis single relay selection under decode-and-forward and Rayleigh fading are assumed. We show that in low signal-to-noise ratio (SNR), FRNs are much more effective in reducing OP than URNs. In high SNR, URNs are almost equally as effective as FRNs in reducing OP. In terms of ergodic capacity, FRNs achieve higher performance than URNs in all SNR regimes. We conclude that from a system design viewpoint, if the aim is to meet certain quality-of-service constraints, FRNs can be reserved to serve low SNR users, while URNs could be employed when channel conditions to destination UTs are more favorable.
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| 8. |
- Pietsch, Christian, et al.
(author)
-
EU FP7 INFSO-ICT-247223 ARTIST4G, D3.5c Moving Relays and Mobility aspects
- 2012
-
Reports (other academic/artistic)abstract
- This deliverable presents analysis and simulation results related to moving relays and mobility optimization for relay enhanced networks. The results reported in this deliverable are ranging from fundamental performance limits expressed in terms outage probability to practical implementations of the moving relay concepts through architecture discussion, coordinated moving relays and network coded moving relays.
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| 9. |
- Wanlu, Sun, 1986, et al.
(author)
-
D2D-based V2V Communications with Latency and Reliability Constraints
- 2014
-
In: 2014 IEEE Globecom Workshops, GC Wkshps 2014; Austin; United States; 8 December 2014 through 12 December. - 9781479974702 ; , s. 1414-1419
-
Conference paper (peer-reviewed)abstract
- Direct device-to-device (D2D) communication has been proposed as a possible enabler for vehicle-to-vehicle (V2V) applications, where the incurred intra-cell interference and the stringent latency and reliability requirements are challenging issues. In this paper, we investigate the radio resource management problem for D2D-based V2V communications. Firstly, we analyze and mathematically model the actual requirements for vehicular communications and traditional cellular links. Secondly, we propose a problem formulation to fulfill these requirements, and then a Separate Resource Block allocation and Power control (SRBP) algorithm to solve this problem. Finally, simulations are presented to illustrate the improved performance of the proposed SRBP scheme compared to some other existing methods.
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| 10. |
- Wanlu, Sun, 1986, et al.
(author)
-
Radio Resource Management for D2D-based V2V Communication
- 2016
-
In: IEEE Transactions on Vehicular Technology. - 0018-9545 .- 1939-9359. ; 65:8, s. 6636-6650
-
Journal article (peer-reviewed)abstract
- Direct device-to-device (D2D) communication has been proposed as a possible enabler for vehicle-to-vehicle (V2V) applications, where the incurred intra-cell interference and the stringent latency and reliability requirements are challenging issues. In this paper, we investigate the radio resource management problem for D2D-based V2V communications. Firstly, we analyze and mathematically model the actual requirements for vehicular communications and traditional cellular links. Secondly, we propose a problem formulation to fulfill these requirements, and then a Separate Resource Block allocation and Power control (SRBP) algorithm to solve this problem. Finally, simulations are presented to illustrate the improved performance of the proposed SRBP scheme compared to some other existing methods.
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| 11. |
- Yutao, Sui, 1984, et al.
(author)
-
Evaluation of Link Adaptation Methods in Multi-User OFDM Systems with Imperfect Channel State Information
- 2011
-
In: Future Network & Mobile Summit 2011, 15 - 17 June 2011, Warsaw, Poland.
-
Conference paper (peer-reviewed)abstract
- Link adaptation has shown to be a method of improving the wireless communication system throughput over quasi-static fading channels. Link adaptation, however, requires channel quality information (CQI) at the transmitter side, which is difficult to obtain accurately. Within the European WINNER project, a low complexity, near optimum, mutual information based adaptive coding and modulation (MI-ACM) link adaptation scheme was proposed. Previous work, however, only focused on evaluating this scheme with perfect CQI and without considering the potential signaling overhead introduced by this algorithm. In this paper, the performance of the MI-ACM algorithm is evaluated and compared to the link adaptation framework used in LTE. A more realistic multi-user scenario is studied by taking the channel prediction error and control signaling constraint into account. Simulation results show that the MI-ACM algorithm is useful only in a few types of scenarios, e.g., system with few users having low average SINR, low velocities with channels presenting substantial frequency selectivity.
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| 12. |
- Yutao, Sui, 1984, et al.
(author)
-
Interference management for moving networks in ultra-dense urban scenarios
- 2015
-
In: Eurasip Journal on Wireless Communications and Networking. - : Springer Science and Business Media LLC. - 1687-1499 .- 1687-1472. ; 2015:1, s. Art. no. 111-
-
Journal article (peer-reviewed)abstract
- The number of users relying on broadband wireless connectivity while riding public transportation vehicles is increasing significantly. One of the promising solutions is to deploy moving base stations on public transportation vehicles to form moving networks (MNs) that serve these vehicular users inside the vehicles. In this study, we investigated the benefits and challenges in deploying MNs in ultra-dense urban scenarios. We identified that the key challenge limiting the performance of MNs in ultra-dense urban scenarios is inter-cell interference, which is exacerbated by the urban canyon effects. To address this challenge, we evaluated different inter-cell interference coordination and multi-antenna interference suppression techniques for MNs. We showed that in using MNs together with effective interference management approaches, the quality of service for users in vehicles can be significantly improved, with negligible impacts on the performance of regular outdoor users.
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| 13. |
- Yutao, Sui, 1984, et al.
(author)
-
Moving cells : A promising solution to boost performance for vehicular users
- 2013
-
In: IEEE Communications Magazine. - 0163-6804 .- 1558-1896. ; 51:6, s. 62-68
-
Journal article (peer-reviewed)abstract
- In future wireless networks, a significant number of users accessing wireless broadband will be vehicular (i.e., in public transportation vehicles like buses, trams, or trains). The Third Generation Partnership Project has started to investigate how to serve these vehicular users cost-effectively, and several solutions have been proposed. One promising solution is to deploy a moving relay node (MRN), on a public transportation vehicle that forms its own cell inside the vehicle to serve vehicular users. By proper antenna placement, an MRN can reduce or even eliminate the vehicular penetration loss that affects communication. Moreover, MRNs can exploit various smart antenna techniques and advanced signal processing schemes, as they are less limited by size and power than regular user equipment. However, there are also challenges in using MRNs, such as designing efficient interference management techniques as well as proper mobility management schemes to exploit the benefit of group handovers for vehicular UE devices served by the same MRN. Nevertheless, initial system-level evaluation results indicate that a dedicated MRN deployment shows great potential to improve the vehicular user experience, and thereby can potentially bring significant benefits to future wireless communication systems.
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| 14. |
- Yutao, Sui, 1984
(author)
-
Moving Networks, a Better Way to Serve Vehicular Users
- 2016
-
Doctoral thesis (other academic/artistic)abstract
- Nowadays, a great number of mobile broadband users are vehicular. It is very common that people are using their mobile devices either for working or entertainment when they are on the go. We are expecting mobile broadband to offer comparable experience everywhere, e.g., at home, in the office or on the go. One of the biggest challenges to serve vehicular users is that their communication is affected by vehicular penetration loss (VPL), which can be very high in well-isolated public transportation vehicles. This thesis investigates how to serve the vehicular users in a cost efficient way by deploying moving relay nodes (MRNs), or moving networks (MNs) on public transportation vehicles. The benefits of using MRNs or MNs are not only that they can circumvent the VPL by proper antenna placement, but also more sophisticated multi-antenna and signal processing schemes can be employed, as public transportation vehicles are less constrained by size and processing power compared to regular mobile devices. First we consider a single cell setup with one vehicular user served by the network. In [Paper A], by analytic analysis, we show that, in order to minimize the end-to-end outage probability, as the VPL increases, a half-duplex relay node needs to be deployed as close as possible to a vehicular user. This also motivates the use of an MRN to serve vehicular users. In [Paper B], we extend the study of using half-duplex MRN in several aspects, where co-channel interference, practical propagation conditions as well as inter-node handover are taken into account. From the study in [Paper B], we show that the use of MRN has great potential to improve the Quality-of-Service (QoS) for the vehicular users that are affected by moderate to high VPL. In [Paper C], we give an overview of existing solutions, and we discuss the benefits of using MRN to serve vehicular users from a system perspective.In the near future, it is expected that more frequency bands at higher frequencies will be freed up for mobile communications, especially for small cells. Therefore, in the second part of the thesis, we extend the study of using half-duplex MRNs to a full-duplex moving network (MN) in an ultra-dense urban deployment scenario. Both MRNs and MNs use wireless backhaul links to communicate with the network and form their own cells to serve the vehicular users. However, MRNs use the same frequency at their access links as the backhaul links, while MNs need dedicated frequency for their access links in order to work in a full-duplex fashion. In [Paper D], we show that the most limiting factor for further improving the performance of MNs in the ultra-dense urban scenario is the complicated inter-cell interference. Therefore, we compare the use of various multiple-antenna techniques at the backhaul receivers of MNs to alleviate the inter-cell interference experienced by the backhaul links of MNs. For the access links of MNs, as they are operating in the same frequency bands as small cells which are densely deployed along the road, we propose to use almost blank subframes (ABSs) to protect the access links of the MNs. By using system level evaluations, we demonstrate that by deploying full-duplex MNs on public transportation vehicles in an ultra-dense urban scenario, the throughput of the vehicular users can be significantly improved, and the impact on regular outdoor users is very limited.Finally, in [Paper E], we propose a novel way to enhance the uplink quality of vehicular users through cooperative communication enabled by device-to-device (D2D) communication. We show that when the vehicular users are affected by moderate to high VPL, by cooperating with each other to enhance their UL communication, the same amount of data can be sent in a shorter time. Therefore, all participants can benefit from the cooperation.
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| 15. |
- Yutao, Sui, 1984
(author)
-
On the Benefits of Moving Relay Nodes in Wireless Networks
- 2012
-
Licentiate thesis (other academic/artistic)abstract
- In order to meet the needs of high speed wireless connections, a new generation of cellular network, i.e., Long Term Evolution (LTE) has been standardized and deployed by the 3rd Generation Partnership Project (3GPP). By employing ad- vanced smart antenna techniques, fast channel dependent scheduling, adaptive coding and modulation, etc., LTE offers a very high peak data rate in ideal conditions. However, the capacity of the LTE network is not evenly distributed, i.e., the cell edge users have much worse throughput than cell center users. The successor of LTE, the LTE-Advanced, aims at both further improve the sys- tem capacity and improve the cell edge user experiences. In order to extend the coverage for heavily shadowed or remote areas, and guarantee good user experiences at certain capacity demanding hotspot areas, a heterogeneous and small cell networks (HetSNets) design paradigm has been introduced in LTE- Advanced systems.In this thesis, we study the impacts of the deployment of a new type of relay node (RN), i.e., moving RN (MRN) on current cellular systems. There are several benefits as well as challenges of using MRNs to serve users inside public transportation vehicles. In a noise limited single cell system, the deploy- ment of MRN can significantly lower the end-to-end outage probability (OP) at the user equipment (UE) on board compared to serving the UE by direct or fixed RN (FRN) assisted transmission. The studies have been extended to more practical setups when considering the impact of co-channel interference. In such scenarios, MRN assisted transmission still greatly outperforms direct transmission and FRN assisted transmission in terms of end-to-end OP, when the vehicular penetration loss (VPL) is moderate to high. Moreover, due to the low transmit power nature of an MRN, it generates much less interference to the UEs outside the vehicle, which is very appreciated in a densely deployed urban scenario, since link availabilities are usually dependent on interference rather than on coverage. Hence using MRNs seems very promising for improving the quality-of-service for vehicular users in future mobile communication systems.
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| 16. |
- Yutao, Sui, 1984, et al.
(author)
-
On the Deployment of Moving Networks in Ultra-dense Urban Scenarios
- 2014
-
In: 2014 1st International Conference on 5G for Ubiquitous Connectivity, 5GU 2014; Levi ResortLevi; Finland; 26 November 2014 through 27 November 2014. - : ICST. - 9781631900556 ; , s. 240-245
-
Conference paper (peer-reviewed)abstract
- In future mobile communication systems, more userswill rely on mobile data services while riding public transportation vehicles for either working or entertainment. To serve these vehicular users effectively, the deployment of moving base stations on public transportation vehicles is considered as one of the most promising solutions. Each public transportation vehicle forms a moving network (MN) inside the vehicle to serve the users on board. In this paper, we study the deployment of MNs in an ultra-dense urban scenario, and we identify that one of the key challenges is the inter-cell interference, which is worsen by the street canyon effects. In order to address this problem, we employ and compare various solutions to enhance the performance of MNs. We show that by using MNs that have advanced multi-antenna systems, the quality of service at the vehicular users is noticeably improved without obvious influence on the performance of regular outdoor users.
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| 17. |
- Yutao, Sui, 1984, et al.
(author)
-
Performance Comparison of Fixed and Moving Relays under Co-channel Interference
- 2012
-
In: 2012 IEEE Globecom Workshops, GC Wkshps 2012; Anaheim, CA; United States; 3 December 2012 through 7 December 2012. - 9781467349413 ; , s. 574-579
-
Conference paper (peer-reviewed)abstract
- In this paper, we study and compare the outage probability (OP) of a vehicular user of dual-hop moving relay node (MRN) assisted transmission, dual-hop transmission assisted by a fixed relay node (FRN), as well as of the baseline single-hop direct transmission under of co-channel interference. For an accurate comparison, we numerically optimize the FRN position which minimizes the average vehicular user OP. When vehicular penetration loss is moderate to high, MRN assisted transmission is shown to greatly outperform transmission assisted by an FRN as well as direct transmission. Hence the use of MRNs is very promising for improving the quality-of-service of vehicular users for future mobile communication systems.
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| 18. |
- Yutao, Sui, 1984, et al.
(author)
-
Performance study of fixed and moving relays for vehicular users with multi-cell handover under co-channel interference
- 2013
-
In: IEEE International Conference on Connected Vehicles and Expo. ; , s. 514-520
-
Conference paper (peer-reviewed)abstract
- In this paper, we investigate the power outage probability (OP) of a vehicular user equipment (VUE) device served by half-duplex decode-and-forward relay nodes (RNs) under co-channel interference. Both moving RNs (MRNs) and fixed RNs (FRNs) are studied, and compared with the baseline, base station (BS) to VUE direct transmission. In order to understand the benefit for vehicular users served by an RN, we consider practical channel models for different involved links as well as the impact of handover (HO) between the BS and the RNs. For an accurate comparison, we present a comprehensive framework to optimize the HO parameters, as well as we numerically optimize the FRN position which minimizes the average power OP at the VUE. FRN shows its advantage to serve its nearby VUEs. However, when vehicular penetration loss is moderate to high, MRN assisted transmission greatly outperforms transmission assisted by an FRN as well as direct transmission. Hence, the use of MRNs is very promising for improving the quality-of-service (QoS) of VUEs in future mobile communication systems.
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| 19. |
- Yutao, Sui, 1984, et al.
(author)
-
The energy efficiency potential of moving and fixed relays for vehicular users
- 2013
-
In: IEEE Vehicular Technology Conference. - 1550-2252. - 9781467361873
-
Conference paper (peer-reviewed)abstract
- In future wireless networks a significant number of wireless broadband users will be vehicular, i.e., they will be in public transportation vehicles like buses, trams or trains. In this paper, we show that the efficient use of relay nodes to serve vehicular users can greatly improve the energy efficiency of the network while maintaining the required quality-of-service (QoS). We consider vehicular users moving along a road within the coverage of a base station (BS). Communication can take place in a single-hop fashion (baseline case) or can be assisted by a single relay node (dual-hop), which can either be a fixed relay node (FRN) deployed at a specific position on the road or a moving relay node (MRN) mounted on top of the vehicle. We compare the required overall transmit energy for direct transmission, FRN and MRN assisted transmission in a noise limited system under Rayleigh fading while assuming an outage probability (OP) target. A lower bound is derived for the required energy of the FRN assisted transmission. It is shown that as the vehicular penetration loss (VPL) increases, both FRN and MRN assisted transmission can significantly lower the overall transmit energy compared to the conventional one-hop case. Moreover, transmission relying on an MRN outperforms the FRN assisted case when VPL is moderate to high.
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| 20. |
- Yutao, Sui, 1984, et al.
(author)
-
The Potential of Moving Relays - A Performance Analysis
- 2012
-
In: IEEE Vehicular Technology Conference. - 1550-2252. - 9781467309905
-
Conference paper (peer-reviewed)abstract
- In this paper we show the potential of moving relaynodes (MRNs) for improving the capacity, reliability and coverage of future wireless networks. To this end we study and compare the performance of single-hop direct transmission, dual-hop MRN assisted transmission as well as dual-hop fixed relay node (FRN) assisted transmission. For an accurate comparison we derive the optimal FRN position minimizing the outage probability (OP)when the user position is known as a function of the pathloss, transmit power and vehicle penetration loss (VPL). The problem is investigated for Rayleigh fading channels and when the cell coverage area is fixed. We show that when VPL is moderate to high, MRN assisted transmission greatly outperforms transmission through FRNs as well as direct transmission, and is very promising for future wireless systems.
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| 21. |
- Yutao, Sui, 1984, et al.
(author)
-
Uplink enhancement of vehicular users by using D2D communications
- 2013
-
In: 2013 IEEE Globecom Workshops, GC Wkshps 2013. - 9781479928514 ; , s. 649-653
-
Conference paper (peer-reviewed)abstract
- In this paper, we discuss one application enabled by device-to-device (D2D) communication for vehicular users inside well isolated public transportation vehicles. We study the feasibility of using D2D communication to enhance the uplink communication for vehicular user equipment (VUE) devices. D2D communication allows fast data exchange among VUE devices, and therefore, a number of VUE devices can cooperate with each other and send data to the base station (BS) together. We employ a generalized co-phasing technique for the cooperation with perterminal power constraint, and compare the energy efficiency of single user direct transmission, and cooperative transmission participated by various number of VUE devices. As the public transportation vehicle moves away from the BS and for large vehicular penetration loss, less energy is required to send the same amount of data of each active VUE in the cooperative transmission than the individual VUE-to-BS communications. Hence VUE devices in well isolated vehicles, especially those ones with limited battery lives, can save energy because of the enhanced uplink communications. © 2013 IEEE.
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