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Cosine-Modulated Multitone for Very-High-Speed Digital Subscriber Lines


In this paper, the use of cosine-modulated filter banks (CMFBs) for multicarrier modulation in the application of very-high-speed digital subscriber lines (VDSLs) is studied. We refer to this modulation technique as cosine-modulated multitone (CMT). CMT has the same transmitter structure as discrete wavelet multitone (DWMT). However, the receiver structure in CMT is different from its DWMT counterpart. DWMT uses linear combiner equalizers, which typically have more than 20 taps per subcarrier. CMT, on the other hand, adopts a receiver structure that uses only two taps per subcarrier for equalization. This paper has the following contributions. (i) A modification that reduces the computational complexity of the receiver structure of CMT is proposed. (ii) Although traditionally CMFBs are designed to satisfy perfect-reconstruction (PR) property, in transmultiplexing applications, the presence of channel destroys the PR property of the filter bank, and thus other criteria of filter design should be adopted. We propose one such method. (iii) Through extensive computer simulations, we compare CMT with zipper discrete multitone (z-DMT) and filtered multitone (FMT), the two modulation techniques that have been included in the VDSL draft standard. Comparisons are made in terms of computational complexity, transmission latency, achievable bit rate, and resistance to radio ingress noise.


  1. 1.

    Lee EA, Messerschmitt DG: Digital Communication. 2nd edition. Kluwer Academic, Boston, Mass, USA; 1994.

    Google Scholar 

  2. 2.

    Proakis JG: Digital Communications. 3rd edition. McGraw-Hill, New York, NY, USA; 1995.

    Google Scholar 

  3. 3.

    Chen WY: DSL: Simulation Techniques and Standards Development for Digital Subscriber Lines Systems. Macmillan, Indianapolis, Ind, USA; 1998.

    Google Scholar 

  4. 4.

    Starr T, Cioffi JM, Silverman PJ: Understanding Digital Subscriber Line Technology. Prentice-Hall, Upper Saddle River, NJ, USA; 1999.

    Google Scholar 

  5. 5.

    Steele R: Mobile Radio Communications. IEEE Press, New York, NY, USA; 1992.

    Google Scholar 

  6. 6.

    Bingham JAC: Multicarrier modulation for data transmission: an idea whose time has come. IEEE Communications Magazine 1990, 28(5):5–14. 10.1109/35.54342

    Article  Google Scholar 

  7. 7.

    xDSL Forum,

  8. 8.


  9. 9.

    ANSI T1E1.4 Working Group,

  10. 10.

    Network and Customer Installation Interfaces—Asymmetric Digital Subscriber Line (ADSL) Metallic Interface T1.413-1998, American National Standards Institute, New York, NY, USA, 1998

  11. 11.

    Radio broadcasting systems; Digital Audio Broadcasting (DAB) to mobile, portable and fixed receivers ETS 300 401, European Telecommunications Standards Institute, 2nd ed., May 1997

  12. 12.

    Digital Video Broadcasting (DVB); Framing structure, channel coding and modulation for digital terrestrial television ETS 300 744, European Telecommunications Standards Institute, March 1997

  13. 13.

    Sjoberg F, Isaksson M, Nilsson R, Odling P, Wilson SK, Borjesson PO: Zipper: a duplex method for VDSL based on DMT. IEEE Transactions on Communications 1999, 47(8):1245–1252. 10.1109/26.780461

    Article  Google Scholar 

  14. 14.

    Mestdagh DG, Isaksson M, Odling P: Zipper VDSL: a solution for robust duplex communication over telephone lines. IEEE Communications Magazine 2000, 38(5):90–96. 10.1109/35.841831

    Article  Google Scholar 

  15. 15.

    Sjoberg F, Nilsson R, Isaksson M, Odling P, Borjesson PO: Asynchronous zipper [subscriber line duplex method]. Proc. IEEE International Conference on Communications (ICC '99), June 1999, Vancouver, British Columbia, Canada 1: 231–235.

    Google Scholar 

  16. 16.

    Committee T1, Working Group T1E1.4 "VDSL Metallic Interface: Part1—Functional rquirements and common specifications," Draft Standard, T1E1.4/2000-009R3, February 2001; and "VDSL Metallic Interface: Part 3—Technical specification of multi-carrier modulation transceiver," Draft Standard, T1E1.4/2000-013R1, May 2000

  17. 17.

    Nilsson R: Digital communication in wireline and wireless environments, M.S. thesis. Luleå University of Technology, Luleå, Sweden; March 1999. available at:

    Google Scholar 

  18. 18.

    Jeong B-J, Yoo K-H: Digital RFI canceller for DMT based VDSL. Electronics Letters 1998, 34(17):1640–1641. 10.1049/el:19981022

    Article  Google Scholar 

  19. 19.

    Cioffi J, Mallory M, Bingham J: Digital RF cancellation with SDMT. ANSI Contribution T1E1.4/96-083, April 1996

    Google Scholar 

  20. 20.

    Cioffi J, Mallory M, Bingham J: Analog RF cancellation with SDMT. ANSI Contribution T1E1.4/96-084, April 1996

    Google Scholar 

  21. 21.

    Cherubini G, Eleftheriou E, Olcer S: Filtered multitone modulation for VDSL. Proc. IEEE Global Telecommunications Conference (GLOBECOM '99), December 1999, Rio de Janeireo, Brazil 2: 1139–1144.

    Google Scholar 

  22. 22.

    Cherubini G, Eleftheriou E, Olcer S, Cioffi JM: Filter bank modulation techniques for very high speed digital subscriber lines. IEEE Communications Magazine 2000, 38(5):98–104. 10.1109/35.841832

    Article  Google Scholar 

  23. 23.

    Cherubini G, Eleftheriou E, Olcer S: Filtered multitone modulation for very high-speed digital subscriber lines. IEEE Journal on Selected Areas in Communications 2002, 20(5):1016–1028. 10.1109/JSAC.2002.1007382

    Article  Google Scholar 

  24. 24.

    Vaidyanathan PP: Multirate Systems and Filter Banks. Prentice-Hall, Englewood Cliffs, NJ, USA; 1993.

    Google Scholar 

  25. 25.

    Sandberg SD, Tzannes MA: Overlapped discrete multitone modulation for high speed copper wire communications. IEEE Journal on Selected Areas in Communications 1995, 13(9):1571–1585. 10.1109/49.475531

    Article  Google Scholar 

  26. 26.

    Tzannes MA, Tzannes MC, Resnikoff H: The DWMT: A Multicarrier Transceiver for ADSL using M-band Wavelet Transforms. ANSI Contribution T1E1.4/93-067, March 1993

    Google Scholar 

  27. 27.

    Tzannes MA, Tzannes MC, Proakis J, Heller PN: DMT systems, DWMT systems and digital filter banks. Proc. IEEE International Conference on Communications (SUPERCOMM/ICC '94), May 1994, New Orleans, La, USA 1: 311–315.

    Google Scholar 

  28. 28.

    Hawryluck M, Yongacoglu A, Kavehrad M: Efficient equalization of discrete wavelet multi-tone over twisted pair. Proc. International Zurich Seminar on Broadband Communications, February 1998, Zurich, Switzerland 185–191.

    Google Scholar 

  29. 29.

    Neurohr N, Schilpp M: Comparison of transmultiplexers for multicarrier modulation. Proc. 4th IEEE International Conference on Signal Processing (ICSP '98), October 1998, Beijing, China 1: 35–38.

    Article  Google Scholar 

  30. 30.

    Viholainen A, Alhava J, Helenius J, Rinne J, Renfors M: Equalization in filter bank based multicarrier systems. Proc. 6th IEEE International Conference on Electronics, Circuits and Systems (ICECS '99), September 1999, Pafos, Cyprus 3: 1467–1470.

    Article  Google Scholar 

  31. 31.

    Govardhanagiri S, Karp T, Heller P, Nguyen T: Performance analysis of multicarrier modulation systems using cosine modulated filter banks. Proc. IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP '99), March 1999, Phoenix, Ariz, USA 3: 1405–1408.

    Article  Google Scholar 

  32. 32.

    Farhang-Boroujeny B, Chin WH: Time domain equaliser design for DWMT multicarrier transceivers. Electronics Letters 2000, 36(18):1590–1592. 10.1049/el:20001092

    Article  Google Scholar 

  33. 33.

    Farhang-Boroujeny B, Lin L: Analysis of post-combiner equalizers in cosine-modulated filter bank-based transmultiplexer systems. IEEE Transactions on Signal Processing 2003, 51(12):3249–3262. 10.1109/TSP.2003.819014

    MathSciNet  Article  Google Scholar 

  34. 34.

    Farhang-Boroujeny B: Multicarrier modulation with blind detection capability using cosine modulated filter banks. IEEE Transactions on Communications 2003, 51(12):2057–2070. 10.1109/TCOMM.2003.820753

    MathSciNet  Article  Google Scholar 

  35. 35.

    Farhang-Boroujeny B: Discrete multitone modulation with blind detection capability. Proc. 56th IEEE Vehicular Technology Conference (VTC '02), September 2002, Vancouver, British Columbia, Canada 1: 376–380.

    Article  Google Scholar 

  36. 36.

    Alhava J, Renfors M: Adaptive sine-modulated/cosine-modulated filter bank equalizer for transmultiplexers. Proc. European Conference on Circuit Theory and Design (ECCTD '01), August 2001, Espoo, Finland

    Google Scholar 

  37. 37.

    Viholainen A, Alhava J, Renfors M: Implementation of parallel cosine and sine modulated filter banks for equalized transmultiplexer systems. Proc. IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP '01), May 2001, Salt Lake City, Utah, USA 6: 3625–3628.

    MATH  Google Scholar 

  38. 38.

    Alhava J, Renfors M: Exponentially-modulated filter bank-based transmultiplexer. Proc. IEEE International Symposium on Circuits and Systems (ISCAS '03), May 2003, Bangkok, Thailand 4: IV-233–IV-236.

    Google Scholar 

  39. 39.

    Borna B, Davidson TN: Efficient filter bank design for filtered multitone modulation. Proc. IEEE International Conference on Communications (ICC '04), June 2004, Paris, France 1: 38–42.

    Google Scholar 

  40. 40.

    Wornell GW: Emerging applications of multirate signal processing and wavelets in digital communications. Proceedings of the IEEE 1996, 84(4):586–603. 10.1109/5.488701

    Article  Google Scholar 

  41. 41.

    Scaglione A, Giannakis GB, Barbarossa S: Redundant filterbank precoders and equalizers. I. Unification and optimal designs. IEEE Transactions on Signal Processing 1999, 47(7):1988–2006. 10.1109/78.771047

    Article  Google Scholar 

  42. 42.

    Lin Y-P, Phoong S-M: ISI-free FIR filterbank transceivers for frequency-selective channels. IEEE Transactions on Signal Processing 2001, 49(11):2648–2658. 10.1109/78.960412

    Article  Google Scholar 

  43. 43.

    Rossi M, Zhang J-Y, Steenaart W: Iterative least squares design of perfect reconstruction QMF banks. Proc. Canadian Conference on Electrical and Computer Engineering (CCECE '96), May 1996, Calgary, Alberta, Canada 2: 762–765.

    Google Scholar 

  44. 44.

    Björck Å: Numerical Methods for Least Squares Problems. SIAM, Philadelphia, Pa, USA; 1996.

    Google Scholar 

  45. 45.

    Brezinski C, Wuytack L: Projection Methods for Systems of Equations. Elsevier, Amsterdam, The Netherlands; 1997.

    Google Scholar 

  46. 46.

    Ng TM, Farhang-Boroujeny B, Garg HK: An accelerated Gauss-Seidel method for inverse modeling. Signal Processing 2003, 83(3):517–529. 10.1016/S0165-1684(02)00449-8

    Article  Google Scholar 

  47. 47.

    Malvar HS: Signal Processing with Lapped Transforms. Artech House, Norwood, Mass, USA; 1992.

    Google Scholar 

  48. 48.

    ETSI : Transmission and Multiplexing (TM); Access transmission systems on metallic cables: Very high speed Digital Subscriber Line (VDSL); Part1: Functional requirements. Technical Specification TS 101 270-1 V1.1.1 (1998-04) 1998.

    Google Scholar 

  49. 49.

    Lin L: Multicarrier communications based on cosine modulated filter banks, M.S. thesis. University of Utah, Salt Lake City, Utah, USA; submitted

  50. 50.

    Cioffi JM: A Multicarrier Primer. ANSI Contribution T1E1.4/91-157, November 1991

    Google Scholar 

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Correspondence to Lekun Lin.

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Lin, L., Farhang-Boroujeny, B. Cosine-Modulated Multitone for Very-High-Speed Digital Subscriber Lines. EURASIP J. Adv. Signal Process. 2006, 019329 (2006).

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