Hello. I'm Yasir Zaki.

Postdoctoral Fellow at New York University Abu Dhabi (NYUAD).

    I have been working for the past five years on research and development of mobile communications (3GPP standards). Some of my research topics are:
  • - Wireless and Cellular Networks (e.g., LTE-A)
  • - Network Virtualization
  • - Transport Congestion Control Protocols
  • - Web enhacements for developing regions

Learn more about me

Resume

I'm a communication engineer. I have been working for the past several years on different industrial and European funded projects such as the 4WARD and SAIL EU projects. My main area of expertise is mobile communication.
I have worked closely with Nokia Siemens Networks (NSN) on the development of different cellular standards
including: UMTS, HSPA, LTE.

Education

PhD in Communication Networks
University of Bremen 2007 - 2012

Graduated with honor "Summa Cum Laude"

MSc in Communication and Information Technology
University of Bremen 2005 - 2007

Graduated first on my class with a CGPA of 4.0.

BSc in Electronics and Communication
University of Baghdad 2000 - 2004

Graduated first on my class with an overall grade of 84%

Work Experience

Postdoctoral Fellow at NYU Abu Dhabi
January 2013 - present
I have started working as a Postdoctoral Fellow in Professor Jay Chen research group at NYU Abu Dhabi. My main research topics focus on LTE-advance and Content Centric Networking (CCN).

Postdoctoral Researcher at University of Bremen
July 2012 - January 2013
Worked as a Postdoctoral research at the University of Bremen. Leading the industrial project work with Nokia Siemens Networks. Working in addition within the FP7 SAIL European project.

Research Associate at University of Bremen
June ​2007 - July 2012
Worked in several industrial and European funded projects. Some of my tasks involved design, implementation and performance evaluations of several algorithms and functionalities, especially in the area of mobile networks, e.g. UMTS, HSDPA, HSUPA and LTE.

My Publications

Books / Book Chapters


1. Y. Zaki, "Future Mobile Communications: LTE Optimization and Mobile Network Virtualization", Springer Book. ISBN 978-3-658-00808-6, 2012
Y. Zaki, Future Mobile Communications: LTE Optimization and Mobile Network Virtualization, urn:nbn:de:gbv:urn:nbn:de:gbv:46-00102749-12, University of Bremen Library, 2012

2. X. Li, Y. Zaki, T. Weerawardane, A. Timm-Giel, C. Görg, and G.C. Malafronte. Use of Traffic Separation Techniques for the Transport of HSPA and R99 Traffic in the Radio Access Network with Differentiated Quality of Service. IGI Global, 2010.

3. X. Li, T. Weerawardane, Y. Zaki, C. Görg, and A. Timm-Giel. Shared Transport for Different Radio Broadband Mobile Technologies. IGI Global, June 2011.

Journal Papers


4. Xi Li, Y. Zaki, T. Weerawardane, A. Timm-Giel, C. Görg, and G. C. Malafronte. Use of Traffic Separation Techniques for the Transport of HSPA and R99 Traffic in the Radio Access Network with Differentiated Quality of Service. In IJBDCN Journal, September 2009.

5. Y. Zaki, T. Weerawardane, X. Li, A. Timm-Giel, G.C. Malafronte, and C. Görg. Performance enhancement due to the tnl congestion control on the simultaneous deployment of both hsdpa and hsupa. In Recent Advances in Communications and Networking Technologies, Journal of Networks, volume 7, 2010.

6. Y. Zaki, L. Zhao, C. Görg, and A. Timm-Giel. Lte mobile network virtualization. In Mobile Networks and Applications (MONET), ACM Journal, pages 1–9. Springer Netherlands, 2011. 10.1007/s11036-011-0321-7.

7. U. Toseef, Y. Zaki, A. Timm-Giel and C. Görg.Optimized resource management using linear programming in integrated heterogeneous networks. In IARIA International Journal on Advances in Networks and Services, June 2013.

Conference Papers


8. M. Khan and Y. Zaki. Dynamic spectrum trade and game-theory based network selection in lte virtualization using uniform auctioning. In Xavier Masip-Bruin, Dominique Verchere, Vassilis Tsaoussidis, and Marcelo Yannuzzi, editors, Wired/Wireless Internet Communications,
volume 6649 of Lecture Notes in Computer Science, pages 39–55. Springer Berlin / Heidelberg, 2011. 10.1007/978-3-642-21560-5_4.

9. M. Li, L. Zhao, Y. Zaki, A. Timm-Giel, and C. Görg. Investigation of network virtualization and load balancing techniques in lte networks. In 2012 IEEE 75th Vehicular Technology Conference: VTC2012-Spring, Yokohama, Japan, May. 2012.

10. X. Li, Y. Zaki, T. Weerawardane, A. Timm-Giel, and C. Görg. Hsupa backhaul bandwidth dimensioning. In Personal, Indoor and Mobile Radio Communications, 2008. PIMRC 2008. IEEE 19th International Symposium on, pages 1 –6, Cannes, France, sept. 2008.

11. Xi Li, Olivier Mehani, Ramón Agüero, Roksana Boreli, Y. Zaki, and Umar Toseef. Evaluating user-centric multihomed flow management for mobile devices in simulated heterogeneous networks. In 4th International Conference on Mobile Networks and Management Monami
2012, Hamburg, Germany, September 2012.

12. S. N. K. Marwat, T. Weerawardane, Y. Zaki, C. Görg, and A. Timm-Giel. Design and performance analysis of bandwidth and qos aware lte uplink scheduler in heterogeneous traffic environment. In 8th International Wireless Communications and Mobile Computing Conference, Limassol, Cyprus, August 2012.

13. S. N. K. Marwat, T. Weerawardane, Y. Zaki, C. Görg, and A. Timm-Giel. Performance evaluation of bandwidth and qos aware lte uplink scheduler. In 10th International Conference on Wired/Wireless Internet Communications, WWIC 2012, Santorini, Greece, June 2012.

14. S. N. K. Marwat, T. Weerawardane, Y. Zaki, C. Görg, and A. Timm-Giel. Performance of bandwidth and qos aware lte uplink scheduler towards delay sensitive traffic. In 17. ITG Fachtagung Mobilkommunikation, Osnabrueck, Germany, May 2012.

15. Y. Zaki, M. Khan, L. Zhao, and C. Görg.Realizing the broker based dynamic spectrum allocation through lte virtualization and uniform auctioning. In Performance Evaluation of Cognitive Radio Networks. Workshop (PE-CRN), Networking 2011, Valencia, Spain, May 2011.

16. Y. Zaki, T. Weerawardane, C. Görg, and A. Timm-Giel. Long term evolution (lte) model development within opnet simulation environment. In OPNET workshop 2011, Washington D.C., USA, August 29-September 1 2011.

17. Y. Zaki, T. Weerawardane, C. Görg, and A. Timm-Giel. Multi-QoS-Aware fair scheduling for LTE. In Vehicular Technology Conference (VTC Spring), 2011 IEEE 73rd, pages 1 –5, may 2011

18. Y. Zaki, T. Weerawardane, X. Li, A. Timm-Giel, G.C. Malafronte, and C. Görg. Effect of the rlc and tnl congestion control on the hsupa network performance. In Communications, Computers and Applications, 2008. MIC-CCA 2008. Mosharaka International Conference on, pages 1 –7, aug. 2008.

19. Y. Zaki, N. Zahariev, T. Weerawardane, C. Görg, and A. Timm-Giel. Optimized service aware lte mac scheduler: Design, implementation and performance evaluation. In OPNET workshop 2011, Washington D.C., USA, August 29-September 1 2011.

20. Y. Zaki, L. Zhao, C. Görg, and A. Timm-Giel. A Novel LTE Wireless Virtualization Framework. In Second International ICST Conference on Mobile Networks And Management (Monami)., Santander, Spain, September 2010. (best student paper award)

21. Y. Zaki, L. Zhao, C. Görg, and A. Timm-Giel. LTE wireless virtualization and spectrum management. In Wireless and Mobile Networking Conference (WMNC), 2010 Third Joint IFIP, pages 1 –6, oct. 2010.

22. Y. Zaki, L. Zhao, J. Jimenez, K. Mengal, A. Timm-Giel, and C. Görg. Towards interoperability among virtual networks in the future internet. In ICT-MobileSummit 2009, Santander Spain, June 2009.

23. Umar Toseef, Y. Zaki, A. Timm-Giel, and C. Görg. Development of simulation environment for multi-homed devices in integrated 3gpp and non-3gpp networks. In 10th ACM International Symposium on Mobility Management and Wireless Access, MobiWac 2012, Paphos Cyprus, October 2012.

24. Umar Toseef, Y. Zaki, A. Timm-Giel, and C. Görg. Optimized flow management using linear programming in integrated heterogeneous networks. In the Seventh International Conference on Systems and Networks Communications ICSNC 2012, Lisbon, Portugal, November 2012. (Best paper award)

25. Umar Toseef, Y. Zaki, A. Timm-Giel, and C. Görg. Uplink qos aware multi-homing in integrated 3gpp and non-3gpp future networks. In 4th International Conference on Mobile Networks and Management Monami 2012, Hamburg, Germany, September 2012.

26. Umar Toseef, Y. Zaki, Liang Zhao, A. Timm-Giel, and C. Görg. Qos aware multi-homing in integrated 3gpp and non-3gpp future networks. In the Seventh International Conference on Systems and Networks Communications ICSNC 2012, Lisbon, Portugal, November 2012.

27. A. Udugama, L. Zhao, Y. Zaki, C. Görg, and A. Timm-Giel. End-to-end performance evaluation of virtual networks using prototype. In Second International ICST Conference on Mobile Networks And Management (Monami), Santander, Spain, September 22-24 2010.

28. T. Weerawardane, Y. Zaki, A. Timm-Giel, G.C. Malafronte, S. Hauth, and C. Görg. Impact of the transport network congestion control on the hsupa performance. In Vehicular Technology Conference, 2009. VTC Spring 2009. IEEE 69th, pages 1 –6, Barcelona, Spain, april 2009.

29. N. Zahariev, Y. Zaki, T. Weerawardane, X. Li, C. Görg, and A. Timm-Giel. Optimized service aware lte mac scheduler with comparison against other well known schedulers. In 10th International Conference on Wired/Wireless Internet Communications, WWIC 2012, Santorini, Greece, June 2012.

30. L. Zhao, M. Li, Y. Zaki, A. Timm-Giel, and C. Görg. Lte virtualization: From theoretical gain to practical solution. In Teletraffic Congress (ITC), 2011 23rd International, pages 71–78, San Francisco, USA, sept. 2011.

31. L. Zhao, Y. Zaki, A. Udugama, U. Toseef, C. Görg, and A. Timm-Giel. Open connectivity services for future networks. In Emerging Technologies for a Smarter World (CEWIT), 2011 8th International Conference Expo on, pages 1–4, nov. 2011.

32. Y. Zaki, T. Weerawardane, X. Li and C. Görg. LTE Radio Schedulers Analytical Modeling using Continuous Time Markov Chains. In the 6th Joint IFIP Wireless and Mobile Networking Conference (WMNC) 2013. Dubai, United Arab Emirates (UAE), April 2013

33. X. Li, Y. Zaki, Y. Dong, N. Zahariev and C. Görg. SON Potential for LTE Downlink MAC Scheduler. In the 6th Joint IFIP Wireless and Mobile Networking Conference (WMNC) 2013. Dubai, United Arab Emirates (UAE), April 2013.

34. A. Singh, M. Xiang, A. Koensgen, Y. Zaki and C. Görg. Enhancing Fairness and Congestion Control in Multipath TCP. In the 6th Joint IFIP Wireless and Mobile Networking Conference (WMNC) 2013. Dubai, United Arab Emirates (UAE), April 2013.

35. T. Pötsch, S. N. K. Marwat, Y. Zaki and C. Görg. Influence of Future M2M Communication on LTE system. In the 6th Joint IFIP Wireless and Mobile Networking Conference (WMNC) 2013. Dubai, United Arab Emirates (UAE), April 2013

36. Y. Zaki, C. Görg and A. Timm-Giel. Future Mobile Communications, LTE Optimization and Mobile Network Virtualization. In 12th Würzburg Workshop on IP: ITG Workshop, Visions of Future Generation Networks (EuroView2012), Würzburg, Germany, July 23rd - July 24th 2012 slides

37. X. Li, O. Mehani, R. Aguero, U. Toseef, Y. Zaki and C. Görg. Evaluating User-Centric Multihomed Flow Management in Multi-User Scenarios. In the third IEEE workshop on Convergence among Heterogeneous Wireless Systems in Future Internet (CONWIRE 2013), Madrid Spain, June 2013

38. T. Pötsch, S. N. K. Marwat, Y. Zaki and C. Görg. Poster Abstract: Performance Evaluation of Machine-to-Machine Communication on Future Mobile Networks in Disaster Scenarios. In the 19th EUNICE Workshop on Advances in Communication Networking, Chemnitz, Germany, 28-30 August 2013

39. S. N. K. Marwat, T. Pötsch, Y. Zaki, T. Weerawardane and C. Görg. Addressing the Challenges of E-healthcare in Future Mobile Networks. In the 19th EUNICE Workshop on Advances in Communication Networking, Chemnitz, Germany, 28-30 August 2013

40. Y. Zaki, T. Weerawardane, S. Hauth, E. Wallmeier and C. Görg. Intelligent Traffic Enforcement for LTE backhaul. In Personal, Indoor and Mobile Radio Conference (PIMRC) 2013, London, United Kingdom, 8-11 Septemebr 2013

41. S.N.K. Marwat. Y. Zaki, J. Chen, A. Timm-Giel and C. Görg. A Novel Machine-to-Machine Traffic Multiplexing in LTE-A System using Wireless In-band Relaying. In 5th International Conference on Mobile Networks and Management (MONAMI) 2013, Cork, Republic of Ireland, September 23–25, 2013

42. S. Marwat, T. Weerawardane, Y. Zaki, and C. Görg, Radio resource allocation for m2m communication in lte uplink scheduling. In the International graduate school for dynamics in logistics, p. 31, 2013.

43. F. Ahmad, S.N.K. Marwat, Y. Zaki, Y. Mehmood, and C. Görg, Machine-to-machine sensor data multiplexing using LTE-advanced relay node for logistics. In 4th international conference on dynamics in logistics (ldic 2014), Bremen Germany 2014.

44. F. Ahmad, S.N.K. Marwat, Y. Zaki, and C. Görg, "Tailoring lte-advanced for m2m communication using wireless inband relay node". In World telecommunications congress 2014 (wtc 2014), Berlin Germany 2014 (accepted).

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My Projects

Current Research


1. Heterogeneous Networks in LTE-A System:Due to the increased requirements on the mobile communication networks to provide higher data rates, better frequency utilization, and increased capacity, the 3GPP standards has introduced several new concepts to tackle these demands. One of the newly added concepts is the use of smaller and low power nodes to increase the overall system capacity and spectral utilization. These nodes include Pico cells and Femto cells, and are sometimes also referred to as Home eNodeBs (HeNB).
Although the use of these nodes provides a very promising solution, however, there are a number of problems that can arise from using these nodes. For example, the HeNBs can be purchased by end-users and enterprises to be used at homes and offices, this means that the location of these nodes will be unplanned and they can be in principle plugged anywhere, this in turn can mess the careful operator radio network planning, since these nodes will be adding interference to the existing macro eNodeBs.
The target of this research is to study and investigate the impact of these small cell nodes on the operator network. The main objective is to come up with a solution that will enable the deployment of these unplanned small cells without affecting the users of the macro/micro base stations. The target is to utilize the benefits of these nodes in an automatic way to achieve an optimal/sub-optimal performance.

2. Coordinated Multi-Point in LTE-A System


Current Student


1. Farhan Ahmad

Former Students


1. Kevork Markarian,"Performance Evaluation of QoS Aware Scheduling Algorithm in C-RAN CoMP for DL LTE-A", Master thesis, March 2014
Abstract: Mobile communication is one of the fastest developing areas nowadays. The increasing number of mobile subscribers, the need for higher data rates to support new applications and the possibility of handover between different technologies have defined the IMT-Advanced requirements. Long Term Evolution-Advanced standardized by 3GPP rel.11 has added new features, such as Carrier Aggregation, enhanced MIMO, Heterogeneous Networks and CoMP. Coordinated Multipoint (CoMP) is a promising method to improve the average cell edge data rate and the system spectrum effeciency, to meet the requirements of 4G mobile communication networks. In the downlink, CoMP can achieve a significant gain with the coordination of multiple base stations. CoMP performance can be effected by network structure, channel estimation methods and the latency created by the limited capacity of the backhaul. After the big success of cloud computing in the IT sector, it is essential to include it into mobile communication via virtualization of the hardware infrastructure and wireless resources. In this thesis, a framework of a two-layer scheduling algorithm is proposed that includes a central unit to act as a hypervisor for C-RAN and supports the joint transmission CoMP technique in the downlink. The scheduling algorithm is multi QoS aware and ensure the performance of different applications. Scenarios in homogenous network are considered and evaluation is performed by a system level simulation using ComNets LTE system module developed with Opnet network simulation software. The results show that the proposed scheme overcomes the delay restrictions of the backhaul network, achieves significant SINR gain to cell edge users of different applications and improves the average cell edge throughput, while keeping the fairness between different QoS requirements.

2. Samira Palipana,"Heterogeneous Networks in LTE-A System", Master thesis, February 2014
Abstract: The continuously growing number of mobile devices in terms of hardware and applications augments the necessity for higher data rates and a larger capacity in wireless communication networks. The Long Term Evolution-Advanced (LTE-A) standard was designed to provide these mobile users with a better throughput, coverage and a lower latency. Instead of providing any enhancements to the macro eNodeBs introduced by its predecessor LTE, the LTE-A standard introduced six new technologies to meet the above mentioned goals such as Carrier Aggregation (CA), Heterogeneous Networks (HetNets), Enhanced MIMO (Multiple Input Multiple Output), Relay Nodes, Coordinated Multi-Point (CoMP) and Self-organizing networks (SONs). This thesis studies a specific area in Heterogeneous Networks, the subject of femtocells. The aim of femtocells is to provide better indoor coverage so as to allow users to benefit from higher data rates while reducing the load on the macro eNodeBs. However, there is an issue with femtocells that may obstruct the performance of femto- and macrocells which is "interference". As femtocells also use the same spectrum as the macrocells and the femtocells are deployed without proper planning, interference from femtocells to macrocells becomes an issue here. In this thesis, the interference from femtocells to macrocells is studied and two novel solutions for the mitigation of this kind of interference are provided, the "Home eNodeB (HeNB) Power Control scheme" and the "Random PRB Selection" scheme. The first method utilizes an analytical approach to mitigate interference based on Channel Quality Indicator (CQI) reports from macrocell users. The other method uses a more simple approach and chooses a random subset of Physical Resource Blocks (PRBs) to allocate to HeNB users so that macrocell users will benefit from a reduced interference level and a larger range of PRBs. The implementation and simulation of the proposed schemes are carried out using the ComNets LTE-A system level simulator in OPNET Modeler software. The results indicate that the two schemes alleviate the macrocell interference significantly with respect to Signal to Interference and Noise Ratio (SINR) and the performance of user applications. The HeNB Power Control scheme performs as a balanced scheme which mitigates the macrocell user interference effectively while securing a better throughput for the HeNB users. In contrast, the Random PRB Selection scheme performs exceptionally well regarding the macrocell user interference mitigation with a slight diminished performance for the home users.

3. Yangyang Dong, "LTE-Advanced: Radio Access Network Resource Management", Master thesis, July 2013
Abstract: The ongoing development of mobile devices and their applications increases the requirements for high data rates and large capacity of the wireless communication networks rapidly. The LTE (Long Term Evolution) system provides the mobile users with a good throughput and a low latency. In order to meet the requirements of the future mobile data traffic, the 3GPP (3rd Generation Partnership Project) has introduced advanced features to the LTE system, such as the Carrier Aggregation (CA), extension of the uplink multiple access, enhanced MIMO (Multiple Input Multiple Output), and the Relay Nodes (RN). The enhanced system is known as the LTE-Advanced (LTE-A) system. This thesis intends to investigate the uplink Radio Access Network (RAN) resource management in LTE-Advanced. It covers three main areas: the Component Carrier Selection (CCS), the Power Control (PC) for the uplink, and the radio resource scheduling. The CCS aims at selecting a proper number of carriers for the mobile terminals; the PC adjusts the uplink transmit Power Spectral Density (PSD); and the scheduling algorithm allocates radio resources to the mobile terminals according to their channel conditions and Quality of Service (QoS) requirements. Literature survey reveals that the CCS is a relatively newer topic with little work done on it. However, the PC for macrocell scenarios has been covered in several research articles and papers. Similarly, several scheduling algorithms have been proposed for LTE and LTEA downlink, whereas the scheduling methods for LTE-A uplink along with the advanced recent features are very rare. In this thesis, a CCS algorithm depending on the path loss and the slow fading during propagation of the radio signals has been developed; based on the channel conditions and the QoS requirements of the users, a Channel and QoS Aware (CQA) uplink scheduler has been designed, which works in a decoupled time and frequency domain. The implementation and simulation of the proposed schemes are performed using the OPNET Modeler. In order to allocate radio resources in compliance with the uplink PC, the scheduling algorithms consider the PSD of the terminals determined by the PC schemes. Two PC algorithms have been implemented and compared in terms of throughput performance in this work. The results illustrate that the proposed CCS algorithm provides a good QoS performance and overall throughput. One of the implemented PC algorithms provides better application experiences. The designed CQA scheduler supports a relatively high overall throughput while guaranteeing the QoS requirements of dierent applications. In addition, it grants some level of fairness among the users.

4. Yangyang Dong, "Investigation of SON for MAC Scheduler in LTE", mini project, March 2013
Abstract: Long Term Evolution (LTE) is the latest release of the mobile network technology standardized by the 3rd Generation Partnership Project (3GPP). It is a set of enhancements to the Universal Mobile Telecommunications System (UMTS). This project is to investigate the effects of the LTE MAC (Medium Access Control) scheduler parameters, and how sensitive the scheduler is against changing these parameters. With the decreased costs associated with obtaining mobile services (especially internet connection), a large number of users are starting to use their internet connection for various applications rather than only voice calls, such as stream videos, download files, etc. One of the most crucial issues in mobile communications is the scarce radio frequencies, which in any case are one of the most expensive parts that the mobile operators have to pay for. Thus, a necessity exists to optimally manage and use these resources in a more efficient way. Therefore, the need to manage all the traffic types used among the users, at the same time to guarantee a reasonable level of QoS, leads to the utilization of MAC scheduler. Furthermore, there are several parameters of the MAC scheduler that can be tuned. The intention of this project is to investigate which parameters can highly improve the performance of the system, for example, to have smooth stream videos or to reduce file download time. Based on the ndings performed in this work, we can identify which scheduler parameters are important for the LTE system, as well as, the thresholds that can trigger the parameters adjustments dynamically. The investigations are performed by simulations with the developed LTE common model using OPNET. The scheduler used is the Optimized Service Aware (OSA) scheduler proposed by ComNets of University of Bremen.

5. Safdar Marwat, "LTE Channel Modeling for System Level Simulations", mini project, September 2011
Abstract: Advancements in mobile communication techniques have helped in introducing various new wireless applications. This has caused an increase in the demand of capacity and performance. Long Term Evolution (LTE) addresses such demands. It exploits Orthogonal Frequency Division Multiplexing (OFDM) for downlink as a digital modulation technique based on dividing the transmission bandwidth into smaller subcarriers. Channel modelling is a fundamental task during the modelling of mobile communication systems. Various channel models have been proposed in the past to be used for simulating the mobile communication systems. With advent of LTE, the need to modify the existing channel models also has surfaced, especially as new frequency bands have been allocated to LTE and new transmission techniques are used. This report analyses various channel models for LTE. Path loss, slow fading and fast fading models are investigated separately within this thesis. The frequency dependence of path loss, the distance correlation of the slow fading, and the frequency/time selectivity of the fast fading are of special interest in the channel modelling. The pros and cons of each model are discussed and the appropriate models are selected for the development of the system level LTE simulator. The overall fading effect of the channel is determined by accumulating the results of the individual path loss, slow fading and fast fading models at a particular time, frequency and location.

6. Nikola Zahariev, "Optimized Service Aware Radio Resource Scheduler in LTE", Master thesis, April 2011
Abstract: The main focus of this thesis is the design and implementation of an LTE Medium Access Control (MAC) scheduler. The LTE MAC scheduler is capable of dierentiating QoS classes and scheduling them according to their priorities and the instantaneous channel conditions of the users; such kind of scheduler is also known as QoS and Channel Aware Scheduler. As pointed out in the previous section, this type of scheduler is crucial for every mobile wireless communication system nowadays. In this thesis the complete downlink scheduling framework - both in Time Domain (TD) and in Frequency Domain (FD) - has been designed and implemented. A scheduling algorithm - Optimized Service Aware (OSA) - has been proposed and its performance compared against popular schedulers like Blind Equal Throughput (BET), Maximum Throughput (MaxT), Weighted Blind Equal Throughput (w-BET), Weighted Maximum Throughput (w-MaxT), Weighted Proportional Fair (w-PF). During the work on this thesis several other work topics have been covered. Implementation of a suitable channel model for the simulation environment, particularly the Fast Fading, has been done. Afterwards, a survey on the Link-to-System (L2S) mapping has been carried out and a suitable interface has been implemented. Further, an HARQ model has been implemented and is now part of the simulator framework. Additionally, considerations and challenges have been pointed out for implementing an uplink scheduler. Some of them include the PRB continuity in the frequency domain as well as the limited buer size of the UE. A Transmission Control Protocol (TCP) mechanism has been proposed for controlling the buer size of greedy FTP users at the transport level.

7. Nikola Zahariev, "Xen-based Migration Performance Analysis", mini project, 2010

8. Sven Meyer, "3GPP Long Term Evolution - Overview of System Specifications in Release 8", mini project, June 2010
Abstract: This thesis will give an overview over the current 3GPP specifications on LTE. In the beginning a short overview over the requirements that were formulated for LTE will be given. The new architecture of the system and changes in the radio interface compared to UMTS Rel. 6 will be explained briefly. The second chapter will focus on the aspects of the physical layer of LTE and covers the topics of the supported frequency bands, transmission bandwidth, and data rates. Afterwards OFDM and SC-FDMA will be described together with the multi antenna transmission schemes that are used to improve the performance of LTE. Chapter three will cover the MAC layer with its logical and transport channels, scheduling and handover. A considerable part of the chapter covers the topics of LTE frame structures and slot structures. Other topics in chapter three are retransmission handling, modulation and coding of channels, discontinuous reception and random access. Chapter four will give an outlook on future developments like LTE-advanced.

9. Khalid Mengal, "Virtual Network Interoperability in the Future Internet", Master thesis, February 2009

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