Led by Prof. Hamid Aghvami Presented by Dr. Xiaoli Chu 1
Introduction Future Work Research Areas Research Projects Statistics 2
King s College London was founded in 1829 and is the fourth oldest university institution in England. King s is based in the heart of London with over 21,000 students from nearly 140 countries, and more than 5,700 employees. King s has played a major role in many of the advances that have shaped modern life, e.g., discovery of the structure of DNA. 3
1980 s Communications Research Group CTR History 1990 s Centre for Telecommunications Research Satellite Communications Physical Layer (Modulation, Coding) Purely Academic Research Emphasis on 3G and beyond, and WLANs/ WMANs/WPANs Research at all layers (Network, Physical, etc) Strong links with Industry 4
Research Teams at the CTR Radio Access Team Network Team Reconfigurability and Cognitive Radio Team 5
Optimal admission control Packet scheduling for B3G systems MAC protocols Sensor networking PHY/MAC for WLANs/WMANs/WPANs UMTS, HSxPA, LTE, WiMAX Relaying Energy-efficient, green radio Space-time block codes (MIMO-OFDM), dirty paper coding Broadcast strategies in multi-user MIMO-OFDM Location tracking Hierarchical cellular structures Cross-layer optimisation of the link layer 6
Mobility management protocols; Network mobility (NEMO) Ad-hoc protocols and networks; mobile ad-hoc networks QoS for IP-based wireless networks; QoS routing Inter-working of networks (e.g., Broadcast, WLANs/WMANs, cellular, ) Vertical handovers Wireless mesh networking Convergence of WLAN and mobile networks Load balancing in IP radio networks Cross-layer optimisation (network/transport layers with lower layers) Peer-to-peer communications over wireless networks Active queue management, wireless fair queuing in IP mobile networks Transport layer protocols; fairness among competing transport protocols Multimedia over wireless 7
Cognitive radio and networking Spectrum sharing and trading; secondary spectrum access; hierarchical spectrum management techniques End-to-end multi-terminal reconfiguration in heterogeneous systems Transport-layer protocols for reconfiguration software downloads over wireless networks; intelligent mode switching Novel resource allocation techniques for secondary spectrum access and cognitive radio - OFDM(A) - MC-CDMA IEEE SCC41 standardisation and protocols 8
30+ researchers - Academics + research staff + PhD students Funding: more than 3M over the past 3 years Published ~300 papers in quality journals and conferences in the past 5 years. The average number of citations per paper is around 3.5. 30 patents in the past 5 years 33 PhD awards in the past 5 years (100% pass rate) Strong collaborative links: (in the past 5 years) - 40+ publications co-authored with other academic institutions - 30+ publications co-authored with industrial partners 9
National Programmes Mobile VCE Core 4: Ubiquitous Services Mobile VCE Core 4: Delivery Efficiency Mobile VCE Core 5: Green Radio International Programmes AROMA (Advanced Resource Management Solutions for Future All-IP Heterogeneous Mobile Radio Environments) IEEE Standardisation Projects (P1900/SCC41) OPTIMOBILE (Cross-layer Optimization for the Coexistence of Mobile and Wireless Networks Beyond 3G) Marie Curie Fellowship Self-NET (Self-Management of Cognitive Future InterNET Elements) 10
To maximise b/s/hz in mobile/wireless communications Three Work Packages: - E1: Optimum Combination of Air-Interface Techniques Develop appropriate combination of air-interface techniques/algorithms for heterogeneous mobile environments - E2: Spectrum Sharing and Enabling via Cognitive Radio Determine/demonstrate practically achievable gains through spectrum sharing techniques - E3: Joint Link and System Optimisation Investigate network topologies and architectures for system optimisation, including cross-layer mechanisms 11
Self-Management of Cognitive Future InterNET Elements An European Commission FP7 STREP, addressing the Strategic Objective ICT-2007.1.6 "New paradigms and experimental facilities" from Challenge 1 "Pervasive and Trusted Network and Service Infrastructures - A novel hierarchical cognitive cycle approach for the selfmanagement of interworking network compartments and individual network elements - Design and specification of future Internet elements around the cognitive cycle; study of implications introduced by autonomic aspects Consortium: University of Athens, Thales, OTE, Fraunhofer FOKUS, Vodafone, King s College London, and Telecom Austria 12
Scenarios Multimedia on Demand - Users are asking for specific contents and are batched to the appropriate network according to availability, cost and capacity constraints. Load Balancing - Traffic load increases as users are using specific services. - Service configuration and traffic distribution algorithm is triggered. - The optimisation results in re-distribution of users to different networks. Always Best Connected - A user is downloading a file. - As the user moves between various wireless network domains, the terminal is auto configured to receive the file. 13
Self-configuring and self-adaptive mechanisms for connectivity management of virtual device components - Self-configuration of network layer and device specific parameters - A re-configurable network stack for memory and energy sensitive devices - A framework for seamless swapping of modules/devices in Linux OS - A network management framework for self-configuring and self-healing - Device management constraints like ACL, policies, security Discovery and selection of - Virtual devices/components - Services/resources - Service discovery gateway Construction and distribution of metadata related to virtual devices or resources Centralized/de-centralized caching of metadata related to virtual devices/resources 14
Mobile VCE Core 5 Programme - 1 PDRA and 4 PhD students of CTR are working on WPs: GR1.2 (energy-efficient architectures), GR1.3 (multihop), GR1.4 (frequency management), GR2.3 (DSP), and GR2.5 (power reduction techniques). 15
Design network architectures for low overall energy use - Cell size - Backhaul method - Femtocell technologies - Multihop and mesh network architectures, delay-tolerant networking Develop techniques to reduce power consumption of wireless communications - Power-efficient radio resource management and signal processing - Interference control - Power-efficient hardware implementation Use of mobility pattern information (UE location, speed and direction) and multimedia traffic characteristics (traffic classification) 16
Maximize system flexibility in uplink and downlink resource allocation - Extend opportunistic scheduling to time, frequency and space dimensions, considering user QoS requirements and interference control. Support advanced and distributed interference mitigation schemes - Enable the network to detect changes, make intelligent decisions, and dynamically configure itself in a distributed fashion. Assess signalling requirements of different radio resource management schemes 17
Advantages of device-to-device communications: offloading cellular systems, reducing battery consumption, increasing bit rate, robustness to infrastructure failures, etc. Design efficient device-to-device communications, with minimal interference to cellular overlay networks. Network information theory - To combat fading and interference in wireless communications - Design the system from an overall network capacity perspective Network coding for multihop communications relayed by fixed or mobile entities (e.g., infrastructure cooperative relaying, device-to-device communications, and cooperation) - To increase throughput through path diversity, energy efficiency, and simplicity of implementation - Practical solutions design - Performance impact evaluation 18
Advanced multiple-antenna systems - CSI feedback (FDD) - MU-MIMO resource allocation and scheduling, combined with modulation/coding schemes and user-specific QoS constraints Coordinated multipoint systems geographically distributed antenna modules coordinate (e.g., through dedicated links) to improve performance of served users in the coordination area - Radio-over-fibre distributed antenna modules are connected to a central station by fibre links - Coordinated multi-cell transmission BSs with coordination criteria managing their overall operation: require a new hierarchical central unit and an extensive revision of related interfaces - Trade-off between performance and added system complexity 19
Spatial antenna techniques - Network MIMO transmission of multiple spatial paths to (from) a mobile from (to) multiple BSs - On the DL, multiple BSs can transmit one or more MIMO paths to a mobile. - On the UL, the transmission by a mobile can be received by one or more BSs. - UL network MIMO can be combined with MU-MIMO and interference cancelation, to allow mobiles in adjacent cells to be assigned the same RBs. One major challenge with network MIMO is the latency for exchange of information between BSs. - Minimum X2 latency in LTE Release 8 is 20 msec, while RBs are assigned on a 1 msec subframe basis. 20
Fractional power control - Control the UL power to compensate for a fraction of path loss - Trade-off between aggregate sector throughput gain and cell-edge user throughput loss in large macrocells - Optimize the power transmitted to and from a mobile, from a network inter-bs or macro diversity perspective Intra- and inter-bs interference cancellation - Opportunistic and organized inter-bs access: spectral, temporal or spatial reuse of scheduled RBs between BSs Opportunistic spectrum access - for spectral reuse within a single macro network - for hierarchal overlay systems such as femto overlays on a macro network Adaptive fractional frequency reuse based on interference levels 21
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