Pulse Shape Design for Ultra-Wideband Radios Using Projections onto Convex Sets

POCS를 이용한 초광대역 무선통신의 펄스파형 설계

  • Lee, Seo-Young (Department of Information and Communication Engineering, Sunmoon University)
  • 이서영 (선문대학교 정보통신공학과)
  • Published : 2008.03.31

Abstract

We propose new pulse shapes for FCC-compliant ultra-wideband (UWB) radios. The projections onto convex sets (POCS) technique is used to optimize temporal and spectral shapes of UWB pulses under the constraints of all of the desired UWB signal properties: efficient spectral utilization under the FCC spectral mask, time-limitedness, and good autocorrelation. Simulation results show that for all values of the pulse duration, the new pulse shapes not only meet the FCC spectral mask most efficiently, but also have nearly the same autocorrelation functions. It is also observed that our truncated (i.e., strictly time-limited) pulse shapes outperform the truncated Gaussian monocycle in the BER performance of binary TH-PPM systems for the same pulse durations. The POCS technique provides an effective method for designing UWB pulse shapes in terms of its inherent design flexibility and joint optimization capability.

FCC 스펙트럼을 만족하는 초광대역(UWB) 무선을 위한 새로운 펄스 파형을 제안한다. POCS(projections onto convex sets) 기술은 UWB 신호의 제반특성(FCC 스펙트럼 마스크하에서의 효율적인 스펙트럼 이용, 시간 제한성, 좋은 자기상관)의 제약 조건하에서 UWB 펄스의 시간 및 스펙트럼의 파형을 최적화한다. 시뮬레이션 결과에 의하면 펄스 파형의 모든 값에 대해 새로운 펄스 파형은 FCC 스펙트럼 마스크를 매우 효율적으로 만족할 뿐만 아니라 거의 동일한 자기상관함수를 갖고 있음을 보여준다. 또한 동일한 펄스폭에 대해 제안된 펄스의 절단된(즉 엄격히 시간 제한된) 펄스 파형은 이진 TH-PPM(time-hoping pulse position modulation) 시스템의 BER 성능에서 절단된 가우시안 모노싸이클(Gaussian monocycle)보다 우수하다. POCS 기술은 이 기술의 본질적인 설계 유연성 및 결합 최적화 능력 관점에서 UWB 펄스 파형 설계에 매우 효과적인 방법을 제공한다.

Keywords

References

  1. R. A. Scholtz, "Multiple access with time hopping impulse modulation," in Proc. Military Communications Conf., Boston, MA, USA, pp. 447-450, Oct. 1993
  2. M. Z. Win and R. A. Scholtz, "Impulse radio: How it works," IEEE Commun. Lett., vol. 2, no. 9, pp. 36-38, Feb. 1998 https://doi.org/10.1109/4234.660796
  3. "FCC Report and Order, In the Matter of Revision of Part 15 of the Commission's Rules Regarding Ultra-Wideband Transmission Systems," FCC-02-48, Apr. 22, 2002
  4. X. Huang and Y. Li, "Performances of impulse train modulated ultra-wideband systems," in Poc. IEEE International Conf. on Communications, vol. 2, pp. 758-762, Apr. 2002
  5. F. Ramírez-Mireles and R. A. Scholtz, "System performance analysis of impulse radio modulation," in Proc. of Radio and Wireless Conf., pp. 67-70, 1998
  6. X. Wu, Z. Tian, T. N. Davidson, and G. B. Giannakis, "Optimal waveform design for UWB radios," in Proc. IEEE International Conf. on Acoustics, Speech, and Signal Processing, pp. 521-524, May. 2004
  7. X. Wu, Z. Tian, T. N. Davidson, and G. B. Giannakis, "Optimal waveform design for UWB radios," IEEE Trans. Signal Process., vo. 54, no. 6, pp. 2009-2021, Jun. 2006 https://doi.org/10.1109/TSP.2006.872556
  8. X. Luo, L. Yang, and G. B. Giannaskis, "Designing optimal pulse-shapers for ultra-wideband radios," J. of Communications and Networks, vol. 5, no. 4, pp. 344-353, Dec. 2003 https://doi.org/10.1109/JCN.2003.6596616
  9. L. B. Michael, M. Ghavami, and R. Kohno, "Multiple pulse generator for ultra-wideband communication using Hermite polynomial based orthogonal pulses," in Proc. IEEE Conf. on Ultra Wideband Systems and Tech., pp. 47-51, May 2002
  10. R. S. Dilmaghani, M. Ghavami, B. Allen, and H. Aghvami, "Novel UWB pulse shaping using prolate spheroidal wave functions," in Proc. Personal, Indoor and Mobile Radio Communications, vol. 1, pp. 602-606, Sept. 2003
  11. B. Parr, B. Cho, K. Wallace, and Z. Ding, "A novel ultra-wideband pulse design algorithm," IEEE Commun. Lett., vol. 7, no. 5, pp. 219-221, May. 2003 https://doi.org/10.1109/LCOMM.2003.812167
  12. G. Lu, P. Spasojevic, and L. Greenstein, "Antenna and pulse designs for meeting UWB spectrum density requirements," in Proc. IEEE Conf. on Ultra Wideband Systems and Tech., pp. 162-166, Nov. 2003
  13. N. C. Beaulieu and B. Hu, "A novel pulse design algorithm for ultra-wideband communications," in Proc. IEEE Global Telecommunications Conf., pp. 3220-3224, 2004
  14. Y. Kim, B. Jang, C. Shin, and B. F. Womack, "Orthonormal pulses for high data rate communications in indoor UWB systems," IEEE Commun. Lett., vol. 9, no. 5, pp. 405-407, May. 2005 https://doi.org/10.1109/LCOMM.2005.1431153
  15. D. C. Youla and H. Webb, "Image restoration by the method of convex projections: Part I - Theory," IEEE Trans. Medical Imaging, vol. MI, pp. 81-94, Oct. 1982.
  16. R. A. Nobakht and M. R. Civanlar, "Optimal pulse shape design for digital communication systems by projections onto convex sets," IEEE Trans. Commun., vol. 434, no. 12, pp. 2874-2877, Dec. 1995
  17. J. Doherty and H. Stark, "Direct-sequence spread spectrum narrowband interference rejection using property restoration," IEEE Trans. Commun., vol. 44, no. 9, pp. 1197-1204, Sept. 1996 https://doi.org/10.1109/26.536925
  18. K. R. Narayanan and J. Doherty, "A convex projections method for improved narrow-band interference rejection in direct-sequence spread-spectrum systems," IEEE Trans. Commun., vol. 45, no. 7, pp. 772-774, Jul. 1997 https://doi.org/10.1109/26.602581
  19. M. Ghavani, L. B. Michael, and R. Kohno, Ultra Wideband Signals and Systems in Communication Engineering, West Sussex, England: Wiley, 2004
  20. M.-G. D. Benedetto and G. Giancola, Understanding Ultra Wide Band Radio Fundamentals, Upper Saddle River, New Jersey: Prentice Hall PTR, 2004