Integer frequency offset detection methods for OFDM-based WLAN systems

ABSTRACT

Recently, a frequency offset estimation method for orthogonal frequency division multiplexing (OFDM) has been proposed by Ren et al. (REA) [9]. The method can estimate an frequency offset for any training symbol structure. In the REA method, however, the integer frequency offset detection probability is rapidly varying according to the fractional frequency offset.

In this paper, we first analyze the REA frequency offset estimation method, and define new detection criteria suitable for integer frequency offset detection. Then, we propose two efficient integer frequency offset estimation methods based on maximum likelihood method. The proposed methods overcome the drawback of the REA method, maintaining its advantage. The numerical results demonstrate that the proposed methods outperform the REA method in terms of the integer frequency offset detection probability.

REFERENCES

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INDEX TERMS

Primary Classification:
  E. Data
  E.4 CODING AND INFORMATION THEORY

Additional Classification:
  C. Computer Systems Organization
  C.2 COMPUTER-COMMUNICATION NETWORKS
      C.2.1 Network Architecture and Design
          Subjects: Wireless communication

  F. Theory of Computation
  F.1 COMPUTATION BY ABSTRACT DEVICES
      F.1.2 Modes of Computation
          Subjects: Probabilistic computation

  G. Mathematics of Computing
  G.3 PROBABILITY AND STATISTICS
      Subjects: Probabilistic algorithms (including Monte Carlo)

General Terms:
Algorithms, Design, Theory

Keywords:
OFDM, estimation, integer frequency offset, training symbol