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Non-iterative Bit Loading Algorithm for OFDM in Independent and Correlated fading

  • Manry, John W. (Naval Air Systems Command) ;
  • Nagaraj, Santosh (Department of Electrical and Computer Engineering, San Diego State University)
  • Received : 2013.04.19
  • Accepted : 2013.11.17
  • Published : 2014.06.30

Abstract

This paper will focus on improving the performance of orthogonal frequency division multiplexing (OFDM) in Rayleigh fading environments. The proposed technique will use a previously published method that has been shown to improve OFDM performance in independent fading, based on ordered sub-carrier selection. Then, a simple non-iterative method for finding the optimal bit-loading allocation was proposed. It was also based on ordered sub-carrier selection. We compared both of these algorithms to an optimal bit-loading solution to determine their effectiveness in a correlated fading environment. The correlated fading was simulated using the JTC channel models. Our intent was not to create an optimal solution, but to create a low complexity solution that can be used in a wireless environment in which the channel conditions change rapidly and that require a simple algorithm for fast bit loading.

Keywords

References

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