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Digital-Carrier Multi-Band User Codes for Baseband UWB Multiple Access  

Yang, Liuqing
Giannakis, Georgios-B.
Publication Information
Abstract
The growing interest towards ultra-wideband (UWB) communications stems from its unique features such as baseband operation, ample multipath diversity, and the potential of enhanced user capacity. But since UWB has to overlay existing narrowband systems, multiple access has to be achieved in the presence of narrowband interference (NBI). However, existing baseband spreading codes for UWB multiple access are not flexible in handling NBI. In this paper, we introduce two novel spreading codes that not only enable baseband UWB multiple access, but also facilitate flexible NBI cancellation. We construct our codes using a single carrier or multiple carriers (SC or MC), which can be implemented with standard discrete-cosine transform (DCT) circuits. With our SC/MC codes, NBI can be avoided by simply nulling undesired digital carriers. Being digital, these SC/MC codes give rise to multiband UWB systems, without invoking analog carriers. In addition, our SC/MC codes enable full multipath diversity, and maximum coding gains. Equally attractive is their capability to reduce the number of interfering users, with simple matched filter operations. Comprehensive simulations are also carried out to corroborate our analysis.
Keywords
ultra-wideband (UWB); diversity gain; coding gain; multipath; RAKE; direct-sequence(DS); single-carrier(SC); multicarrier(MC); narrowband interference(NBI); multi-user interference(MUI); discrete cosine transform(DCT);
Citations & Related Records

Times Cited By Web Of Science : 13  (Related Records In Web of Science)
Times Cited By SCOPUS : 16
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1 M. Z. Win and R. A. Scholtz, 'On the energy capture of ultrawide band-width signals in dense multipath environments,' IEEE Commun. Lett.,vol. 2, no. 9, pp. 245-247, Sept. 1998   DOI   ScienceOn
2 D. Cassioli et al. 'Performance of low-complexity rake reception in arealistic uwb channel,' in Proc. Int. Conf. Commun., New York, NY, USA,Apr. 28-May 2, 2002, pp. 763-767
3 C. J. Le Martret and G. B. Giannakis, 'All-digital impulse radio for wire-less cellular systems,' IEEE Trans. Cnmmun., vol. 50, no. 9, pp. 1440-1450, Sept. 2002   DOI   ScienceOn
4 A. A. M. Saleh and R. A. Valenzuela, 'A statistical model for indoormultipath propagation,' IEEE J. Select. Areas Commun., vol. 5, no. 2,pp. 128-137, Feb. 1987   DOI   ScienceOn
5 Z. Wang, 'Multi-carrier ultra-wideband multiple-access with good re-silience against multiuser interference,' in Proc. Conf. Info. Sciences &Systems, Baltimore, MD, Mar. 12-14. 2003
6 M. Z. Win and R. A. Scholtz, 'Ultra wide bandwidth time-hopping spread-spectmm impulse radio for wireless multiple access communications,'IEEE Trans. Commun., vol. 48, no. 4, pp. 679-691, Apr. 2000   DOI   ScienceOn
7 G. Durisi, J. Romme, and S. Benedetto, 'Performance of TH and DSUWB multiaccess systems in presence of multipath channel and narrow-band interference,' in Proc. International Workshop on Ultra WidebandSystems, Oulu, Finland, June 2-5, 2003
8 L. Yang and G. B. Giannakis, 'Multi-stage block-spreading for impulseradio multiple access through ISI channels,' IEEE J. Setect. Areus Com-mun., vol. 20, no. 9, pp. 1767-1777, Dec. 2002   DOI
9 J. Proakis, Digital Communications, McGraw-Hill, New York, 4th ed.,Feb.2001
10 Z. Wang and G. B. Giannakis, 'Complex-field coding for OFDM overfading wireless channels,' IEEE Trans. Inform. Theory, vol. 49, no. 3.pp. 707-720, Mar. 2003   DOI   ScienceOn
11 R. A. Scholtz, 'Multiple access with time-hopping impulse modulation,'in Proc. MILCOM Conf., Boston. MA, USA, Oct. 11-14, 1993. pp. 447-450
12 Z. Wang and G. B. Giannakis, 'A simple and general parameterizationquantifying performance in fading channels,' IEEE Trans. Cummun.,vol. 51, no. 8, pp.1389-1398,Aug. 2003   DOI   ScienceOn
13 B. M. Sadler and A. Swami, 'On the performance of UWB and DSspread spectrum communication systems,' in Proc. IEEE Conf. on UltraWideband Systems and Technologies. Baltimore, MD, May 20-23, 2002,pp. 289-292
14 H. Sari and G. Karam, 'Orthogonal frequency-division multiple accessand its application to catv network,' ETT, vol. 9, pp. 507-516, Nov./Dec1998
15 L. Yang and G. B. Giannakis, 'Analog space-time coding for multi-antenna ultra-wideband transmissions,' IEEE Trans. Commun., 2004 (to appear)
16 J. R. Foerster, 'The performance of a direct-sequence spread ultra wide-band system in the presence of multipath, narrowband interference, andmultiuser interference,' in Proc. IEEE Conf. UItra Wideband Systems andTechnolosies, Baltimore, MD, USA. May 20-23, 2002, pp. 87-92