The Transactions of the Korean Institute of Electrical Engineers D (대한전기학회논문지:시스템및제어부문D)

The Korean Institute of Electrical Engineers (대한전기학회)
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A Rotational Decision-Directed Joint Algorithm of Blind Equalization Coupled with Carrier Recovery for 32-QAM Demodulation

회전결정 경계를 이용한 32-QAM 목조용 반송파 복구와 채널등화의 Joint 알고리즘

  • 송진호 (명지대학 정보제어공학과) ;
  • 황유모 (명지대학 정보통신공학과)
  • Published : 2002.02.01
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Abstract

We introduce a rotational decision-directed joint algorithm of blind equalization coupled with carrier recovery for 32-QAM demodulation with high symbol rate. The proposed carrier recovery, which we call a rotational decision-directed carrier recovery(RDDCR), removes the residual phase difference by rotating the decision boundary for the kth received symbol by the frequency detector output of the (k-1)th received symbol. Since the RDDCR includes the function of PLL loop filter by rotating the decision boundary, it gives a simpler demodulator structure. The rotational decision-directed blind equalization(RDDBE) with the rotated decision boundary based on the Stop-and-Go Algorithm(SGA) operated during tracking the frequency offset by the RDDCR and removes intersymbol interference due to multipaths and channel noise. Test results show that symbol error rate of $10^{-3}$ is obtained before the forward error correction when SNR equals 15dB with 150KHz of carrier frequency offset and two multipaths, which is the channel condition for 32-QAM receiver.

Keywords

References

  1. Sato, 'A method of self-recovering equalization for multi-level amplitude modulation systems,' IEEE Trans. Comm., vol. COM-23, pp. 679-682, June 1975
  2. A. Benveniste and M. Goursat, 'Blind Equalizers,' IEEE Trans. Comm., vol. COM-32, no. 8, pp. 871-883, Aug.1984
  3. D. N. Godard, 'Self recovering equalization and carrier tracking in two-dimensional data communication system,' IEEE Trans. Comm., vol. COM-35, pp.1867-1875, Nov. 1980
  4. G. Picchi and G. Prati, 'Blind equalization and carrier recovery using a 'stop-and-go' decision-directed algorithm.' IEEE Trans. Comm., vol. COM-35, pp. 877-887, Sep. 1987
  5. Y.S.Choi, H.Hwang, and D.I.Song, 'Adaptive blind equalization coupled with carrier recovery for HDTV modem,' IEEE Trans. Consumer Electronics, vol. 39, no.3, Aug.1993 https://doi.org/10.1109/30.234610
  6. H.Hwang and K.B.Park, 'New AFC tracking algorithms for digital DBS receiver,' IEEE Trans. Consumer Electronics, vol.42, no.3, Aug. 1996 https://doi.org/10.1109/30.536146
  7. Grand Alliance HDTV system specification, Version 2.0, December 1994