| 1. |
- Boldi, Mauro, et al.
(författare)
-
CELTIC CP5-026 WINNER+, D1.8 Intermediate Report on CoMP (Coordinated Multi-Point) and Relaying in the Framework of CoMP.
- 2009
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- This deliverable is an intermediate report on CoMP (Coordinated Multi-Point) and on Relaying in the Framework of CoMP. It describes the second set of innovations encompassing concepts about promising principles or ideas as well as detailed innovative techniques in the framework of WINNER+ system concept. For each concept, the associated benefits as well as the corresponding requirements on the system architecture and protocols, measurements and signalling, are considered. Regarding CoMP algorithms, focus is put on schemes with reduced requirements in terms of backhauling considering two categories: “Coordinated Beamforming”, and “Joint Processing”. As for relaying, a relay-assisted interference channel, and a distributed LDPC coding for a Decode and Forward relay are introduced.
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| 2. |
- Botella Mascarell, Carmen, 1979, et al.
(författare)
-
A low-complexity joint power control and beamforming algorithm for the downlink of multi-user W-CDMA coordinated systems
- 2009
-
Ingår i: Proc. IEEE International Workshop on Signal Processing Advances for Wireless Communications (SPAWC09), June 2009. - 9781424436965 ; , s. 226-230
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Konferensbidrag (refereegranskat)abstract
- The downlink of aW-CDMA system with coordination betweenseveral base stations is considered throughout this paper. Within the framework of the power minimization problem, two Joint Power Control and Optimal Beamforming (JPCOB) algorithms have already been proposed in previous works. However, one of the major challenges associated with network coordination is the design of algorithms which result in low-complexity requirements as the number of users increases. In this paper, one of the previous JPCOBalgorithms is modified in order to obtain a low-complexity solution by reducing the amount of feedback required from the users in the system. The performance of this algorithm is then compared with the previous JPCOB solutions. Simulation results show that the low-complexity algorithm equals the performance of the previous solutions for a given number of coordinated base stations. However,it suffers a severe penalty for scenarios with high SINR requirements at the users. In order to overcome this drawback, two iterative schemes based on the particular structure of the matrices involved in the power control updating step are proposed. Moreover, these schemes could be seen as efficient and computationally simple scheduling techniques.
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| 3. |
- Botella Mascarell, Carmen, 1979, et al.
(författare)
-
EU FP7 INFSO-ICT-247223 ARTIST4G, D1.3 Innovative scheduling and cross-layer design techniques for interference avoidance
- 2011
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- This document provides an overview of the proposed innovations and activities in Task 1.2 of Work Package 1 (WP1) of the ARTIST4G project, related to interference avoidance. Focus is on the technical approaches applicable at layer 2, which are grouped into five different classes of innovations related to clustering & user grouping, inter-cell interference coordination, coordinated scheduling, scheduling for joint processing and gametheory based scheduling. Descriptions of the proposed innovations are given including basic ideas, potential of performance, simulation results, realization options and possible implementation restrictions.
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| 4. |
- Botella Mascarell, Carmen, 1979, et al.
(författare)
-
On the performance of joint processing schemes over the cluster area
- 2010
-
Ingår i: IEEE Vehicular Technology Conference Spring, Taipei, Taiwan, May 2010. - 1550-2252. - 9781424425181 ; 2010-January, s. 1-5
-
Konferensbidrag (refereegranskat)abstract
- In this paper, three joint processing schemes for the downlink are characterized and compared within a cluster of base stations. The motivation of this study is to analyze the performance of these schemes over the cluster area, as a first step towards designing an adaptive joint processing scheme supporting dynamic usage scenarios. Each one of the analyzed schemes, the centralized, partial and distributed joint processing approaches, requires a different amount of available channel knowledge at the transmitter side, inter-base information exchange and feedback from the users. In addition, these schemes show varying capabilities to serve the users depending on their location in the cluster area. Therefore, in a real scenario, an adaptive joint processing scheme encompassing the three schemes could be used by the cluster of base stations. Simulation results show that, assuming coherent transmission, the centralized joint processing scheme outperforms with 25% the partial joint processing scheme and with 50% the distributed joint processing approach in the cell edge when a backhaul-load weighted average sum-rate per cell metric is taken into account.
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| 5. |
- Chen, Xin, 1980, et al.
(författare)
-
Improved resource allocation strategy in SU-CoMP network
- 2011
-
Ingår i: The Journal of China Universities of Posts and Telecommunications. - 2210-5123. ; 18:4, s. 7-12
-
Tidskriftsartikel (refereegranskat)abstract
- Coordinated Multi-Point transmission and reception (CoMP) for single user, named as SU-CoMP, is considered as an efficient approach tomitigate inter-cell interference in Orthogonal Frequency Division Multiple Access (OFDMA) systems. Two prevalent approaches in SU-CoMP areCoordinated Scheduling (CS) and Joint Processing (JP). Although JP in SU-CoMP has been proved to achieve a great link performanceimprovement for the cell-edge user, efficient Resource Allocation (RA) on the system level is quite needed. However, so far limited work has beendone considering JP, and most existing schemes achieved the improvement of cell-edge performance at cost of the cell-average performancedegradation compared to the single cell RA. In this paper, a two-phase strategy is proposed for SU-CoMP networks. CS and JP are combined toimprove both cell-edge and cell-average performance. Compared to the single cell RA, simulation results demonstrate that, the proposed strategyleads to both higher cell-average and cell-edge throughput.
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| 6. |
- Chowdappa, V.P., et al.
(författare)
-
Distributed channel prediction for multi-agent systems
- 2017
-
Ingår i: IEEE International Conference on Communications. - 1550-3607.
-
Konferensbidrag (refereegranskat)abstract
- Multi-agent systems (MAS) communicate over a wireless network to coordinate their actions and to report their mission status. Connectivity and system-level performance can be improved by channel gain prediction. We present a distributed Gaussian process regression (GPR) framework for channel prediction in terms of the received power in MAS. The framework combines a Bayesian committee machine with an average consensus scheme, thus distributing not only the memory, but also computational and communication loads. Through Monte Carlo simulations, we demonstrate the performance of the proposed GPR.
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| 7. |
- D'Amico, Valeria, et al.
(författare)
-
Advanced interference management in ARTIST4G: Interference Avoidance
- 2010
-
Ingår i: European Wireless Technology Conference, Paris, France, September 2010. - 9782874870187 ; , s. 21-24
-
Konferensbidrag (refereegranskat)abstract
- This paper gives an overview of the objectives and current research activities on interference avoidance in the EC funded research project ARTIST4G. It is the main objective of the ARTIST4G Work Package 1 (WP1), to build forward on the 3GPP LTE Release 8 baseline, proposing a novel fair mobile broadband technological framework in which to design innovative, practical, scalable and cost-effective interference avoidance solutions. This paper provides an overview of the fundamental classes of innovations studied in ARTIST4G Work Package 1 (WP1) and presents some performance results obtained by means of numerical simulations and test-bed measurements run in the field.
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| 8. |
- D’Amico, Valeria, et al.
(författare)
-
EU FP7 INFSO-ICT-247223 ARTIST4G, D1.1 Definitions and architecture requirements for supporting interference avoidance techniques
- 2010
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- It is the main objective of the ARTIST4G Work Package 1 (WP1), to design innovative interference avoidance solutions by means of transmitter signal processing, scheduling and/or cross layer techniques. Such an approach will enable to identify optimal strategies also taking into account the practical implications on the real system. The major impacts of the WP1 innovations on the radio access network and on the mobile system interfaces, together with constraints due to practical implementations, will be analyzed in this deliverable. This deliverable will be a reference for the work in ARTIST4G Work Package 4 (WP4).A set of guiding questions used to precise the requirements for WP4 has been considered for each new cooperation/coordination functionality. Answers to these questions are provided in this deliverable by grouping the different classes of WP1 innovations into 4 categories with similar requirements on the radio access architecture. For each question, current, expected, minimum and maximum targets of the requirement will be given, helping to ensure that the range of all possible values for all the innovations are taken into account.
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| 9. |
- D’Amico, Valeria, et al.
(författare)
-
EU FP7 INFSO-ICT-247223 ARTIST4G, D1.2 Innovative advanced signal processing algorithms for interference avoidance
- 2010
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- This document provides an overview of the proposed innovations and activities in Task 1.1 of Work Package 1 (WP1) of the ARTIST4G project, related to interference avoidance. Focus is on the technical approaches applicable at the physical layer, which are grouped into four different classes of innovations related to single-cell multi-user MIMO schemes, multi-cell multi-user MIMOschemes, advanced 3D beamforming and enabling functionalities. Descriptions of the proposed innovations are given including basic ideas, potential of performance, simulation results, realization options and possible implementation restrictions.
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| 10. |
- Klockar, Annika, et al.
(författare)
-
Utility as a User Selection Criterion for Coordinated Multi-Point Systems
- 2013
-
Ingår i: 2013 IEEE 24th International Symposium on Personal Indoor and Mobile Radio Communications (PIMRC). - London : IEEE conference proceedings. ; , s. 3123-3128, s. 3123-3128
-
Konferensbidrag (refereegranskat)abstract
- Coordinated multipoint (CoMP) transmission and reception techniques have been proposed to combat inter-cell interference in cellular systems and, hence, to increase the data rates. Due to the overhead introduced, not all users may be served with CoMP. In this paper, we focus on how to select users for joint processing CoMP under limited backhaul capacity. The evaluated user selection schemes take user experience into account, quantified by the utility of Internet application types. We propose a heuristic algorithm utility based user selection that has low computational complexity. Utility based user selection and maximize utility, which maximizes the sum utilities, are compared to maximize rate, which maximizes the sum data rates. A range of traffic mixes and user locations are evaluated. The simulation results indicate that resources required for CoMP are more efficiently used if the user selection is based on utility rather than on maximizing the total data rate. If utility is taken into account a higher total utility can in many cases be achieved for the same limited backhaul capacity.
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| 11. |
- Klockar, Annika, et al.
(författare)
-
Utility of Joint Processing Schemes
- 2010
-
Ingår i: 2010 7th International Symposium on Wireless Communication Systems (ISWCS 2010). - : IEEE Communications Society. - 9781424463152 ; , s. 76-80, s. 76-80
-
Konferensbidrag (refereegranskat)abstract
- Joint processing between base stations has been shown as an efficient technique to mitigate inter-cell interference and increase data rates, in particular at the cell edges. In this paper, we evaluate the utility of Internet applications in a joint processing enabled cluster of base stations. Utility is used to quantify system performance as experienced by the end user. In particular, the utility of three joint processing schemes for the downlink is characterized and compared within the cluster area. The qualitative results indicate that joint processing can significantly improve the utility of hard real-time and adaptive applications. For elastic applications, joint processing is not worthwhile, since almost as high utility is achieved also with conventional single base station assignment
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| 12. |
- Lakshmana, Tilak Rajesh, 1980, et al.
(författare)
-
Partial joint processing for frequency selective channels
- 2010
-
Ingår i: IEEE Vehicular Technology Conference. - 1550-2252. - 9781424435746
-
Konferensbidrag (refereegranskat)abstract
- In this paper, we consider a static cluster of base stations where joint processing is allowed in the downlink. The partial joint processing scheme is a user-centric approach where subclusters or active sets of base stations are dynamically defined for each user in the cluster. In frequency selective channels, the definition of the subclusters or active set thresholding of base stations can be frequency adaptive (per resource block) or non-adaptive (averaged over all the resource blocks). Frequency adaptive thresholding improves the average sum-rate of the cluster, but at the cost of an increased user data interbase information exchange with respect to the non-adaptive frequency thresholding case. On the other hand, the channel state information available at the transmitter side to design the beamforming matrix is very limited and rank deficiency problems arise for low values of active set thresholding and users located close to the base station. To solve this problem, an algorithm is proposed that defines a cooperation area over the cluster where the partial joint processing scheme can be performed, frequency adaptive or non-adaptive, for a given active set threshold value.
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| 13. |
- Lakshmana, Tilak Rajesh, 1980, et al.
(författare)
-
Partial Joint Processing with Efficient backhauling in Coordinated MultiPoint Networks
- 2012
-
Ingår i: IEEE Vehicular Technology Conference. - 1550-2252. - 9781467309905
-
Konferensbidrag (refereegranskat)abstract
- Joint processing between base stations is a promising technique to improve the quality of service to users at the cell edge, but this technique poses tremendous requirements on the backhaul signaling capabilities. Partial joint processing is a technique aimed to reduce feedback load, in one approach the users feed back the channel state information of the best links based on a channel gain threshold mechanism. However, it has been shown in the literature that the reduction in the feedback load is not reflected in an equivalent backhaul reduction unless additional scheduling or precoding techniques are applied. The reason is that reduced feedback from users yields sparse channel state information at the Central Coordination Node. Under these conditions, existing linear precoding techniques fail to remove the interference and reduce backhaul, simultaneously, unless constraints are imposed on scheduling. In this paper, a partial joint processing scheme with efficient backhauling is proposed, based on a stochastic optimization algorithm called particle swarm optimization. The use of particle swarm optimization inthe design of the precoder promises efficient backhauling with improved sum rate.
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| 14. |
- Lakshmana, Tilak Rajesh, 1980, et al.
(författare)
-
Partial joint processing with efficient backhauling using particle swarm optimization
- 2012
-
Ingår i: Eurasip Journal on Wireless Communications and Networking. - : Springer Science and Business Media LLC. - 1687-1499 .- 1687-1472. ; 2012
-
Tidskriftsartikel (refereegranskat)abstract
- In cellular communication systems with frequency reuse factor of one, user terminals(UT) at the cell-edge are prone to intercell interference. Joint processing is one of the coordinated multipoint transmission techniques proposed to mitigate this interference. In the case of centralized joint processing, the channel state information fed back by the users need to be available at the central coordination node for precoding. The precoding weights (with the user data) need to be available at the corresponding base stations to serve the UTs. These increase the backhaul traffic. In this article, partial joint processing (PJP) is considered as a general framework that allows reducing the amount of required feedback. However, it is difficult to achieve a corresponding reduction on the backhaul related to the precoding weights, when a linear zero forcing beamforming technique is used. In this work, particle swarm optimization is proposed as a tool to design the precoding weights under feedback and backhaul constraints related to PJP.The precoder obtained with the objective of weighted interference minimization allows some multiuser interference in the system, and it is shown to improve the sum rate by 66% compared to a conventional zero forcing approach, for those users experiencing low signal to interference plus noise ratio.
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| 15. |
- Lakshmana, Tilak Rajesh, 1980, et al.
(författare)
-
Scheduling for Backhaul Load Reduction in CoMP
- 2013
-
Ingår i: IEEE Wireless Communications and Networking Conference, WCNC. - 1525-3511. - 9781467359399 ; , s. 227-232
-
Konferensbidrag (refereegranskat)abstract
- Coordinated multi-point (CoMP) transmission has received a lot of attention, as a way to improve the system throughput in an interference limited cellular system. For joint processing in CoMP, the user equipments (UEs) need to feed back the channel state information (CSI), typically to their serving base stations (BSs). The BS forwards the CSI to a central coordination node (CCN) for precoding. These precoding weights need to be forwarded from the CCN to the corresponding BSs to serve the UEs. In this work, a feedback load reduction technique is employed via partial joint processing to alleviate the CSI feedback overhead. Similarly, to achieve backhaul load reduction due to the precoding weights, scheduling approaches are proposed. The state of the art block diagonalization solution is compared with our proposed constrained and unconstrained scheduling. Our main contribution is the method of choosing the best subset of the BSs and UEs at the CCN that yields the best sum rate under the constraint of efficient backhaul use. In particular, with constrained scheduling, the choice of a smaller subset proportionally reduces the backhaul load. Simulation results based on a frequency selective WINNER II channel model, show that our proposed constrained scheduling outperforms the block diagonalization approach in terms of the average sum rate per backhaul use.
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| 16. |
- Li, Jingya, 1986, et al.
(författare)
-
A novel frequency reuse scheme for coordinated multi-point transmission.
- 2010
-
Ingår i: IEEE Vehicular Technology Conference Spring, Taipei, Taiwan, May 2010. - 1550-2252. - 9781424425198 ; , s. 1-5
-
Konferensbidrag (refereegranskat)abstract
- Coordinated Multi-Point (CoMP) transmission is considered in 3GPP LTE-Advanced as a key technique to improve the cell-edge performance. In order to support joint resource allocation among coordinate cells in CoMP systems, efficient frequency reuse schemes need to be designed. However, most of the existing frequency reuse schemes are not suitable for CoMP transmission due to not considering multi-cell joint transmission scenario in their frequency reuse rule. To solve this problem, a cooperative frequency reuse (CFR) scheme is proposed in this paper, which divides the cell-edge area of each cell into two types of zones, and defines a frequency reuse rule to support CoMP transmission for users in these zones. Compared with the conventional soft frequency reuse (SFR) scheme, simulation results demonstrate that the CFR scheme reduces the blocking probability by more than 50%, and improves the cell-edge throughput by 30~40%, with 5~9% additional cell-average throughput.
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| 17. |
- Li, Jingya, 1986, et al.
(författare)
-
Downlink Radio Resource Allocation for Coordinated Cellular OFDMA Networks
- 2010
-
Ingår i: IEICE Transactions on Communications. - 1745-1345. ; E93B:12, s. 3480-3488
-
Tidskriftsartikel (refereegranskat)abstract
- Base station coordination is considered as a promising technique to mitigate inter-cell interference and improve the cell-edge performance in cellular orthogonal frequency division multiple-access (OFDMA) networks. The problem to design an efficient radio resource allocation scheme for coordinated cellular OFDMA networks incorporating base station coordination has been only partially investigated. In this contribution, a novel radio resource allocation algorithm with universal frequency reuse is proposed to support base station coordinated transmission. Firstly, with the assumption of global coordination between all base station sectors in the network, a coordinated subchannel assignment algorithm is proposed. Then, by dividing the entire network into a number of disjoint coordinated clusters of base station sectors, a reduced-feedback algorithm for subchannel assignment is proposed for practical use. The utility function based on the user average throughput is used to balance the efficiency and fairness of wireless resource allocation. System level simulation results demonstrate that the reduced-feedback subchannel assignment algorithm significantly improves the cell-edge average throughput and the fairness index of users in the network, with acceptable degradation of cell-average performance.
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| 18. |
- Li, Jingya, 1986, et al.
(författare)
-
Joint Scheduling and Power Control in Coordinated Multi-Point Clusters
- 2011
-
Ingår i: IEEE Vehicular Technology Conference. - 1550-2252. - 9781424483273 ; , s. Art. no. 6092837-
-
Konferensbidrag (refereegranskat)abstract
- In this paper, we address the problem of designing a joint scheduling and power control algorithm in a downlink coordinated multi-point (CoMP) cluster supporting CoMP joint transmission. The objective is to maximize the cell-edge throughput under per-point power constraints. By an analytical derivation, binary power control is proved to be the optimal solution for any given selected user group. Utilizing this analytical result, a centralized and a semi-distributed version of joint user selection and power control algorithms are proposed. Compared to algorithms without considering joint transmission and algorithms without considering power control, simulation results show that the proposed algorithms achieve a good trade-off between joint transmission and interference coordination, which helps to improve the cell-edge performance.
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| 19. |
- Li, Jingya, 1986, et al.
(författare)
-
Multi-Beam Cooperative Frequency Reuse for Coordinated Multi-Point Systems
- 2010
-
Ingår i: Journal of China Universities of Posts and Telecommunications. - 1005-8885. ; 17:6, s. 11-18
-
Tidskriftsartikel (refereegranskat)abstract
- Coordinated Multi-Point (CoMP) transmission is considered in 3GPP LTE-Advanced as a key technique to mitigate inter-cell interference and improve the cell-edge performance. To apply CoMP joint transmission effectively, efficient frequency reuse schemes need to be designed to support resource management cooperation among coordinated cells. However, most of the existing frequency reuse schemes are not suitable for CoMP systems due to not considering multi-point cooperative transmission scenario in their frequency reuse rules. In addition, the restrictions of frequency resources in those schemes result in high blockingprobability. To solve the above two problems, a multi-beam cooperative frequency reuse (MBCFR) scheme is proposed in this paper, which reuses all the available frequency resources in each sector and supports multi-beam cooperative transmission for cell-edge users. Besides, the blocking probability is proved to be efficiently reduced. Then, a frequency-segment-sequence based MBCFR scheme is introduced to further reduce the inter-cell interference. System level simulations demonstrate that the proposedscheme results in higher cell-edge average throughput and cell-average throughput with lower blocking probability.
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| 20. |
- Li, Jingya, 1986, et al.
(författare)
-
Power Allocation for Two-Cell Two-User Joint Transmission
- 2012
-
Ingår i: IEEE Communications Letters. - 1558-2558 .- 1089-7798. ; 16:19, s. 1474-1477
-
Tidskriftsartikel (refereegranskat)abstract
- In this paper, we develop a power allocation scheme for the downlink of a two-cell two-user joint transmission system. The objective is to maximize the sum rate under per-cell power constraints. We study a worst case scenario where the carrier phases between the two base stations are un-synchronized, so that joint transmission must be performed without precoding. The derived power allocation scheme is remarkably simple, i.e., each cell transmits with full power to only one user. Note that joint transmission is still possible, when two cells select the same user for data transmission. Moreover, we prove that, in this scenario, the joint transmission case happens with higher probability when the maximum transmit power is high, or the two users are in the overlapped cell-edge area.
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| 21. |
- Li, Jingya, 1986, et al.
(författare)
-
Resource allocation for clustered network MIMO OFDMA systems
- 2012
-
Ingår i: Eurasip Journal on Wireless Communications and Networking. - : Springer Science and Business Media LLC. - 1687-1499 .- 1687-1472. ; 2012
-
Tidskriftsartikel (refereegranskat)abstract
- In this paper, we address the resource allocation problem for the downlink of a large network MIMO OFDMA system with 3-sector base stations (BSs). The system is statically divided into a number of disjoint clusters of sectors. A two-step resource allocation scheme is proposed involving the inter-cluster and the intra-cluster levels. As a first step or inter-cluster level, two cooperative frequency reuse approaches are designed to mitigate the inter-cluster interference. A user partition method is proposed to divide the users of each cluster into cluster-edge and cluster-center users. To balance the cell-edge and the cell-average performance, a fairness jug function is introduced to determine the frequency partition of the cooperative frequency reuse approaches. Then, as a second step or intra-cluster level, a utility-based joint scheduling and power allocation algorithm is proposed for each cluster, to maximize the sum utility of all users in the cluster under per-sector power constraints. Zero-forcing joint transmission is used across multiple sectors within the same cluster. Simulation results show that the proposed scheme can efficiently reduce the inter-cluster interference and provide considerable performance improvement in terms of both the cell-edge and cell-average user data rate. The proposed two-step resource allocation scheme can be implemented independently in each cluster without inter-cluster information exchange, which is an attractive property for practical systems, since it reduces both the network signaling overhead and the computational complexity.
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| 22. |
- Li, Jingya, 1986, et al.
(författare)
-
Resource allocation for OFDMA systems with multi-cell joint transmission
- 2012
-
Ingår i: 2012 IEEE 13th International Workshop on Signal Processing Advances in Wireless Communications, SPAWC 2012. Cesme, 17-20 June 2012. - 9781467309714 ; , s. 179-183
-
Konferensbidrag (refereegranskat)abstract
- This paper considers the downlink resource allocation of a coordinated multi-cell cluster in OFDMA systems with universal frequency reuse. Multi-cell joint transmission is considered via zero-forcing precoding. Furthermore, joint optimization of the user selection and power allocation across multiple subchannels and multiple cells is studied. The objective is to maximize the weighted sum rate under per-base-station power constraints. Based on general duality theory, two iterative resource allocation algorithms are proposed and compared with the optimal solution, which requires an exhaustive search of all possible combinations of users over all subchannels. Simulation results show that the two proposed algorithms achieve a performance very close to the optimal, with much lower computational complexity. In addition, we show that joint user set selection across multiple subchannels significantly improves the system performance in terms of the weighted sum rate.
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| 23. |
- Roger, Sandra, et al.
(författare)
-
Recent advances in MIMO wireless systems
- 2009
-
Ingår i: Waves. - 1889-8297. ; 1, s. 115-123
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- In the next years, one of the most significant technological developments that will lead to the new broadband wireless generation is the communication via Multiple-Input Multiple-Output (MIMO) systems. MIMO systems are known to provide an increase of the maximum rate, reliability and coverage of current wireless communications, without additional bandwidth or transmit power. For these reasons, one of the research lines at the iTEAM research Institute is focused on this kind of wireless systems. This paper presents an overview of MIMO wireless techniques, highlighting the aspects of them where our research is mainly concentrated. Especially, the problems of efficient detection in point to point MIMO systems and beamforming in coordinated MU-MIMO systems are discussed. Finally, some solutions to these problems that have been carried out at the iTEAM are addressed.
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| 24. |
- Svensson, Tommy, 1970, et al.
(författare)
-
CELTIC CP5-026 WINNER+, D1.9 Final Innovation Report
- 2010
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- This deliverable is the final innovation report from the innovation workpackage in WINNER+. The document describes the latest innovations and their assessment as well as summarizes the innovations developed in the work package during the project. We analyze the suitability of these innovations as technology enablers for improving current systems, in particular IMT Advanced and beyond.
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| 25. |
- Thiele, Lars, et al.
(författare)
-
Scheduling-Assisted Joint Processing for CoMP in the Framework of the WINNER+ Project
- 2010
-
Ingår i: Proc. Future Network & MobileSummit 2010, June 2010, Florence, Italy..
-
Konferensbidrag (refereegranskat)abstract
- The goal of this paper is to present the main achievements reached within the WINNER+ project concerning, in particular, clustering as a way to improve thefeasibility of joint processing schemes as enablers of coordinated multipoint solutions. Three different approaches are presented. First, a single and static cluster of base stations is considered. In this case, a user-centric partial joint processing scheme isproposed to reduce with respect to a fully centralized approach both the inter-base information exchange and feedback from the users. Second, a dynamic and network centric clustering approach is presented. It is shown that substantial gains can be obtained with respect to a static clustering scenario when a central unit jointly createsthe clusters of collaborating base stations, schedules the users in these clusters and calculates the beamforming coefficients and the power allocation. Finally, a dynamicclustering technique is combined with multi-antenna receivers. In addition, a concept for a scalable channel state information feedback is also presented.
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