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Blind Hopping Phase Estimator in Frequency-Hopped FM and BFSK Systems

  • Kim, Myungsup (Industry-Academic Cooperation Foundation, Mokpo National University) ;
  • Seong, Jinsuk (Industry-Academic Cooperation Foundation, Mokpo National University) ;
  • Lee, Seong-Ro (Departement of Information & Electronics Engineering, Mokpo National University)
  • Received : 2014.07.04
  • Accepted : 2014.09.30
  • Published : 2015.02.01

Abstract

A blind hopping phase estimator is proposed for the demodulation of received signals in frequency-hopping spread spectrum systems. The received signals are assumed to be bandwidth limited with a shaping filter, modulated as frequency modulation (FM) or binary frequency shift keying (BFSK), and hopped by predetermined random frequency sequences. In the demodulation procedure in this paper, the hopping frequency tracking is accomplished by choosing a frequency component with maximum amplitude after taking a discrete Fourier transform, and the hopping phase estimator performs the conjugated product of two consecutive signals and moving-average filtering. The probability density function and Cramer-Rao low bound (CRLB) of the proposed estimator are evaluated. The proposed scheme not only is very simple to implement but also performs close to the CRLB in demodulating hopped FM/BFSK signals.

Keywords

References

  1. M.K. Simon et al., "Spread Spectrum Communicaion Handbook," New York: McGraw Hill, 2002.
  2. C.-Q. Liu, X.-L. Hu, and Y.-Y. Zhang, "Blind Multiuser Detection Algorithm for Asynchronous MFSK/FFH-MA System," Int. Conf. Wireless Commun., Netw. Mobile Comput., Wuhan, China, Sept. 22-24, 2006, pp. 1-4.
  3. H. Fan, Y. Guo, and Y. Xu, "A Novel Algorithm of Blind Detection of Frequency Hopping Signal Based on Second-Order Cyclostationarity," Congress Image Signal Process., vol. 5, Sanya, China, May 27-30, 2008, pp. 399-402.
  4. X.-Q. Liu, J.-L. Li, and X.-L. Ma, "An EM Algorithm for Blind Hop Timing Estimation of Multiple FH Signals Using an Array System with Bandwidth Mismatch," IEEE Trans. Veh. Technol., vol. 56, no. 5, Sept. 2007, pp. 2545-2554. https://doi.org/10.1109/TVT.2007.899960
  5. Y. Lei, Z. Zhong, and Y. Wu, "A New Hop Duration Blind Estimation Algorithm for Frequency-Hopping Signals," IEEE Pacific-Asia Workshop Comput. Intell. Ind. Appl., Wuhan, China, Dec. 19-20, 2008, pp. 695-699.
  6. Z.-C. Sha et al., "Online Hop Timing Detection and Frequency Estimation of Multipath FH Signals," ETRI J., vol. 35, no. 5, Oct. 2013, pp. 748-756. https://doi.org/10.4218/etrij.13.0112.0787

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