An Efficient Circulant MIMO Equalizer for CDMA Downlink: Algorithm and VLSI Architecture

  • Yuanbin Guo
  • Jianzhong(Charlie) Zhang
  • Dennis McCain
  • Joseph R. Cavallaro
Open Access
Research Article
Part of the following topical collections:
  1. Implementation Aspects and Testbeds for MIMO Systems


We present an efficient circulant approximation-based MIMO equalizer architecture for the CDMA downlink. This reduces the direct matrix inverse (DMI) of size Open image in new window with Open image in new window complexity to some FFT operations with Open image in new window complexity and the inverse of some Open image in new window submatrices. We then propose parallel and pipelined VLSI architectures with Hermitian optimization and reduced-state FFT for further complexity optimization. Generic VLSI architectures are derived for the Open image in new window high-order receiver from partitioned Open image in new window submatrices. This leads to more parallel VLSI design with Open image in new window further complexity reduction. Comparative study with both the conjugate-gradient and DMI algorithms shows very promising performance/complexity tradeoff. VLSI design space in terms of area/time efficiency is explored extensively for layered parallelism and pipelining with a Catapult C high-level-synthesis methodology.


Information Technology Quantum Information Design Space Matrix Inverse Complexity Reduction 


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Copyright information

© Guo et al. 2006

Authors and Affiliations

  • Yuanbin Guo
    • 1
  • Jianzhong(Charlie) Zhang
    • 1
  • Dennis McCain
    • 1
  • Joseph R. Cavallaro
    • 2
  1. 1.Nokia Research CenterIrvingUSA
  2. 2.Department of Electrical and Computer Engineering, George R. Brown School of EngineeringRice UniversityHoustonUSA

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