Presentation on the implementation of a real-time wireless MIMO system Based on a Sphere Decoder. (EUSIPCO'2006)

6. Introduction Objectives 1.- Integration of the sphere decoder algorithm in the complete MIMO platform: a.- Platform for validating and comparing different implementations of the Sphere Decoder algorithm. b.- Complexity analysis. 2.- Evaluation of the BER and throughput degradation due to: a.- Fixed point resolution. b.- Estimation and synchronization errors. c.- Validation maintaining the flat channel assumption: c1.- Low-rate real burst transmissions. c2.- High-rate channel emulator.

8. Sphere Decoder System Model

9. Sphere Decoder Concept

10. Sphere Decoder Algorithm

11. Sphere Decoder Algorithm

12. Sphere Decoder Implementation work at the Univ. of Edinburgh ZF Control Partial Distance Partial Candidates Unit Sphere Constraint Detection Internal Memory

13. Sphere Decoder Implementation work at the Univ. of Edinburgh

15. MIMO Prototyping Platform Hardware

21. Real-Time Implementation Task partitioning 2x2 16-QAM MIMO System PCI-based communication with host software

24. Results Resources Algorithm Mults Slices %Slices Transmitter 0 1,320 5.3% Receiver 74 11,923 48.3% Sync. & Ch. Estimation 18 2,693 10.9% Inversion & Cholesky dec. 33 4,608 18.6% Sphere Decoder 23 3,370 13.7% Channel Emulator 20 1,771 7.2% Comms & Control signals 0 1,542 6.2% Total Used 96 16,556 67.0% Total Availaible 216 24,696

25. Results Performance

26. Results Throughput

29. Thank you!

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32. Extras