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Outline

Title
Abstract
Chapter 1: Introduction
Chapter 2: Literature Review and Background
Diversity Combining Methods
Overview of Relay Protocols
Summary
Conclusion and Future Work
Conclusion
Future Work
References
All Topics
Engineering
Electrical and Electronic Engineering

Space-time coded cooperation in WirelessNetworks

Profile image of samir sakrsamir sakr

2014

Abstract

Nowadays, the concept of spatial diversity and cooperative networks attract a lot of interest because they improve the reliability of transmission in wireless networks. Spatial diversity is achieved when multiple antennas are at the transmitter. With great growth and demand for high speed high data rate wireless communication, more and more antennas are required. In order to achieve maximum diversity, these antennas should be well separated so that the fading on each link is uncorrelated. This condition makes it difficult to have more than two antennas on a mobile terminal. The relay's cooperation helps increase the diversity order without extra hardware cost. However, its main inconvenience is the use of multiple time slots compared to the direct link transmission. In this thesis, we develop a cooperation model which is composed of three terminals: source, relay and destination. The transmitters (source and relay) are composed of 2 antennas at the transmitter and the receivers (relay and destination) have 4 antennas. In the first proposed model, transmitters and decoders are composed of an Alamouti encoder and decoder respectively. In the second model, we also add a turbo encoder at transmitters and iterative decoding takes place at receivers. In both cases, the transmission cycle is composed of two time slots and the decode and forward (DF) protocol is applied. Multiple scenarios are considered by changing the environment of the CHAPTER 5: CONCLUSION AND FUTURE WORK .

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  1. LOS Environment ................................................................................... viii 3.3.1.2 NLOS Environment.................................................................................
  2. 3.2 Case 2: Performance in function of the position of the relay .....................
  3. 3.2.1 LOS Environment ...................................................................................
  4. 3.2.2 NLOS Environment.................................................................................
  5. Uplink Environment....................................................................................
  6. Downlink Environment ...............................................................................
  7. 4 Summary ........................................................................................................... CHAPTER 4: TURBO CODED SPACE-TIME COOPERATION ..................................................
  8. 1 System model ....................................................................................................
  9. 1.1 Phase 1 ........................................................................................................
  10. 1.2 Phase 2 ........................................................................................................
  11. 1.3 Decoding at destination...............................................................................
  12. 2 Power allocations ..............................................................................................
  13. 3 Space-time coded cooperation with Turbo-code ..............................................
  14. 3.1 Case 1: Relay at equal distance between source and destination ................
  15. 3.1.1 LOS Environment ...................................................................................
  16. 3.1.2 NLOS Environment.................................................................................
  17. 3.2 Case 2: Performance in function of the position of the relay .....................
  18. 3.2.1 LOS Environment ...................................................................................
  19. 3.2.2 NLOS Environment.................................................................................
  20. Uplink Environment....................................................................................
  21. Downlink Environment .............................................................................
  22. 4 Comparison of space-time code and Turbo coded space-time cooperation ... ix
  23. 4.1 Case 1: Relay at equal distance between source and destination ..............
  24. 4.1.1 LOS Environment .................................................................................
  25. 4.1.2 NLOS Environment...............................................................................
  26. 4.2 Uplink Environment..................................................................................
  27. 4.3 Downlink Environment .............................................................................
  28. 5 Summary ......................................................................................................... References
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