Efficient Integer Frequency Offset Estimation Architecture for Enhanced OFDM Synchronization

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Pham, Thinh Hung ; Fahmy, Suhaib A ; McLoughlin, Ian Vince (2016)

An integer frequency offset (IFO), in orthogonal\ud frequency-division multiplexing (OFDM) systems, causes a circular\ud shift of the sub-carrier indices in the frequency domain.IFO\ud can be mitigated through strict RF front-end design but this\ud is challenging and expensive. Therefore, IFO is estimated and\ud removed at baseband, allowing the RF front-end specification\ud to be relaxed, thus reducing system cost. For applications\ud susceptible to Doppler shift, and multi-standard radios requiring\ud wide frequency range access, careful RF design may be\ud insufficient without IFO estimation. This paper proposes a novel\ud approach for IFO estimation with reduced power consumption\ud and computational cost. A four-fold resource sharing architecture\ud reduces computational cost, while a multiplierless technique and\ud carefully optimised wordlengths yield further power reduction\ud while maintaining a good accuracy. The novel method is shown\ud to achieve excellent performance, similar to the theoretically\ud achievable bound. In fact, performance is significantly better\ud than conventional techniques, while being much more efficient.\ud When implemented for IEEE 802.16-2009, the proposed method\ud saves 78% power over the conventional technique on low-power\ud FPGA devices. The method is applicable to IEEE 802.11 and\ud IEEE 802.22.
  • References (25)
    25 references, page 1 of 3

    [1] M. Morelli, A. D'Andrea, and U. Mengali, “Frequency ambiguity resolution in OFDM systems,” IEEE Communications Letters, vol. 4, no. 4, pp. 134-136, Apr. 2000.

    [2] M. Park, N. Cho, J. Cho, and D. Hong, “Robust integer frequency offset estimator with ambiguity of symbol timing offset for OFDM systems,” in Proc. Vehic. Techn. Conf. (VTC), 2002, pp. 2116-2120.

    [3] E.-S. Shim and Y.-H. You, “OFDM integer frequency offset estimator in rapidly time-varying channels,” in Asia-Pacific Conf. on Commun., 2006, pp. 1-4.

    [4] T.-H. Kim and I.-C. Park, “Low-power and high-accurate synchronization for IEEE 802.16d systems,” IEEE Trans. on Very Large Scale Integration (VLSI) Systems, vol. 16, no. 12, pp. 1620-1630, Dec. 2008.

    [5] M. Morelli and M. Moretti, “Integer frequency offset recovery in OFDM transmissions over selective channels,” IEEE Transactions on Wireless Communications, vol. 7, no. 12, pp. 5220-5226, Dec. 2008.

    [6] D. Toumpakaris, J. Lee, and H.-L. Lou, “Estimation of integer carrier frequency offset in OFDM systems based on the maximum likelihood principle,” IEEE Trans. on Broadcasting, vol. 55, no. 1, pp. 95-108, Mar. 2009.

    [7] C. Shahriar, M. La Pan, M. Lichtman, T. Clancy, R. McGwier, R. Tandon, S. Sodagari, and J. Reed, “PHY-Layer Resiliency in OFDM Communications: A Tutorial,” IEEE Communications Surveys Tutorials, vol. 17, no. 1, pp. 292-314, 2015.

    [8] H. Nogami and T. Nagashima, “A frequency and timing period acquisition technique for OFDM systems,” in Sixth IEEE Inter. Symp. on Personal, Indoor and Mobile Radio Communications (PIMRC), vol. 3, Sep. 1995.

    [9] D. Li, Y. Li, H. Zhang, L. Cimini, and Y. Fang, “Integer frequency offset estimation for OFDM systems with residual timing offset over frequency selective fading channels,” IEEE Trans. on Vehicular Technology, vol. 61, no. 6, pp. 2848-2853, Jul. 2012.

    [10] M. Cummings and S. Haruyama, “FPGA in the software radio,” IEEE Communications Magazine, vol. 37, no. 2, pp. 108-112, Feb. 1999.

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