BWRC Publications

Citation
Omar Bakr, Mark Johnson, Raghuraman Mudumbai, Upamanyu Madhow. "Interference suppression in the presence of quantization errors". Allerton Conference on Communication, Control, and Computing, September, 2009.

Abstract
Multi-element antennas offer the possibility of increasing the spatial reuse of wireless spectrum by “nulling” out interfering signals. However, the interference suppression performance is highly sensitive to small errors in the gains applied to the antenna elements. In this paper, we examine in detail the effect of one specific source of error that arises from quantizing array weights. We show that a simple approach based on scalar quantization that ignores the correlation of the quantization errors fails to fully utilize the interference suppression capability of the array: the residual interference level does not decrease with the number of antennas. Unfortunately, the optimum approach to computing the weights involves vector quantization over a space that grows exponentially with the number of antennas and number of quantization bits, and is therefore computationally intractable. We propose instead a simple suboptimal method that greedily optimizes SIR coefficient by coefficient. Simulations show that this greedy approach provides substantial SIR gains over the naive approach, with SIR growing polynomially in the number of antennas. We derive analytical bounds that indicate that even larger SIR gains (exponential in the number of antennas) are potentially achievable, so that finding tractable algorithms that improve upon our suboptimal approach is an important open problem.

Electronic downloads

• allerton09_camera_ready.pdf · application/pdf · 216 kbytes

Citation formats

• HTML

  Omar Bakr, Mark Johnson, Raghuraman Mudumbai, Upamanyu
  Madhow. <a
  href="http://bwrc.eecs.berkeley.edu/php/pubs/pubs.php/1143.html">Interference
  suppression in the presence of quantization
  errors</a>, Allerton Conference on Communication,
  Control, and Computing, September, 2009.

• Plain text

  Omar Bakr, Mark Johnson, Raghuraman Mudumbai, Upamanyu
  Madhow. "Interference suppression in the presence of
  quantization errors". Allerton Conference on Communication,
  Control, and Computing, September, 2009.

• BibTeX

  @inproceedings{BakrJohnsonMudumbaiMadhow2009,
      author = {Omar Bakr and Mark Johnson and Raghuraman Mudumbai
                and Upamanyu Madhow},
      title = {Interference suppression in the presence of
                quantization errors},
      booktitle = {Allerton Conference on Communication, Control, and
                Computing},
      month = {September},
      year = {2009},
      URL = {http:///php/pubs/pubs.php/1143.html}
  }
  

Posted by Omar Bakr on Oct 6, 2009..

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