Hardware Architectures for WCDMA and MIMO Wireless Communications Systems

WCDMA (Wideband Code Division Multiple Access) is typically considered as one of the most critical application of next-generation telecommunication systems. The main idea of WCDMA is to share the communication support between several users by scrambling user symbol with a pseudo-noise code. This access technique adapts the signals to the communication support by spreading its spectrum. The complexity of the algorithms requires architectural exploration to evaluate performance needs.

Our experiments rely mainly on the use of the SignalMaster prototyping platform that allows applications described using Simulink to be executed on a special-purpose board including a DSP processor and a FPGA chip (SignalMaster platform from Lyrtech Inc. company). Different implementations of the WCDMA. emitter-receiver have been realized. This research has been a preliminary step in the study of fast estimation techniques for the design of SoC. We have studied the arithmetic aspects for the WCDMA receiver implementation. The aim is to find the fixed-point specification which maintains the application performances and minimizes the operator word-length. This specification has been obtained with our approach for floating-point to fixed-point conversion. The real performances have been measured through fixed-point simulation.

In the framework of a joint research program with the LRTS laboratory at Laval university, Québec, Canada (Prof. S. Roy), we have worked on the design of flexible MIMO (Multiple Input Multiple Output) techniques adapted to the WCDMA context.

  1. H.N. Nguyen, D. Menard, and O.Sentieys. Design of Optimized Fixed-point WCDMA Receiver. In Proc. of the XVII European Signal and Image Processing Conference (EUSIPCO’09), Glascow, Scotland, August 2009. EURASIP. [ pdf ]
  2. H.-N. Nguyen, D. Menard, and O. Sentieys. Dynamic precision scaling for low power WCDMA receiver. In Proc. of the IEEE International Symposium on Circuits and Systems, ISCAS 2009, pages 205–208, Taipei, Taiwan, May 2009. [ pdf ]
  3. D. Menard, M. Guitton, S. Pillement, and O. Sentieys. Design and Implementation of WCDMA Platforms: Challenges and Trade-offs. In International Signal Processing Conference (ISPC’03), Dallas, US, April 2003. [ pdf ]
  4. D. Menard, M. Guitton, P. Quemerais, and O. Sentieys. Efficient Implementation of a WCMA Rake Receiver on the TMS320C64x. In 37th Asilomar Conference on Signals, Systems and Computers, Monterey, US, November 2003. [ pdf ]
  5. L. Bélanger, S. Roy, T. Saïdi, and O. Sentieys. Prototyping a MIMO W-CDMA system using a system-level approach. In Proceedings of the International Signal Processing Conference (ISPC) and Global Signal Processing Expo (GSPx), Santa Clara, USA, September 2004. [ pdf ]