Adaptive modulation techniques for duplex OFDM transmission

The design tradeoffs of turbo-coded burst-by-burst adaptive orthogonal frequency division multiplex (OFDM) wideband transceivers are analyzed. We demonstrate that upon aiming for a higher throughput a higher proportion of low-quality OFDM subcarriers has to be used for the transmission of inherently vulnerable high-order modem modes, transmitting several bits per subcarrier. Upon invoking turbo coding and adjusting the modem mode switching regime near-error-free performance can be achieved at the cost of a reduced throughput. Various blind modem mode detection techniques have also been investigated and the most complex channel coding trellis-based detection algorithm was found to be the most powerful. Last, the design tradeoffs of spectral pre-equalization have been explored and quantified. We concluded that AOFDM provides a convenient framework for adjusting the required target integrity and throughput both with and without turbo channel coding.

[1]  C. W. Wyatt-Millington,et al.  Simple coding scheme to reduce peak factor in QPSK multicarrier modulation , 1995 .

[2]  Christer Östberg,et al.  A system for test of multiaccess methods based on OFDM , 1994, Proceedings of IEEE Vehicular Technology Conference (VTC).

[3]  Robert F. H. Fischer,et al.  A new loading algorithm for discrete multitone transmission , 1996, Proceedings of GLOBECOM'96. 1996 IEEE Global Telecommunications Conference.

[4]  Lajos Hanzo,et al.  Constant-rate Turbo-coded and Block-coded Orthogonal Frequency Division Multiplex Videophony over UMTS , 1998 .

[5]  H. Rohling,et al.  Performance of an OFDM-TDMA mobile communication system , 1996, Proceedings of Vehicular Technology Conference - VTC.

[6]  Lajos Hanzo,et al.  Turbo-coded Orthogonal Frequency Division Multiplex transmission of 8 kbps encoded speech , 1997 .

[7]  Kin K. Leung,et al.  Power control for wireless packet voice with application to EDGE system , 2000, Globecom '00 - IEEE. Global Telecommunications Conference. Conference Record (Cat. No.00CH37137).

[8]  R. Chang Synthesis of band-limited orthogonal signals for multichannel data transmission , 1966 .

[9]  J. Cavers An analysis of pilot symbol assisted modulation for Rayleigh fading channels (mobile radio) , 1991 .

[10]  T. Wilkinson,et al.  Block coding scheme for reduction of peak to mean envelope power ratio of multicarrier transmission schemes , 1994 .

[11]  Lajos Hanzo,et al.  Block Turbo Coded Burst-by-Burst Adaptive Modems , 1999 .

[12]  Lajos Hanzo,et al.  Optimisation of switching levels for adaptive modulation in slow Rayleigh fading , 1996 .

[13]  Andrea J. Goldsmith,et al.  Adaptive coded modulation for fading channels , 1998, IEEE Trans. Commun..

[14]  Lajos Hanzo,et al.  Upper-Bound Performance of Radial Basis Function Decision Feedback Equalised Burst-by-Burst Adaptive Modulation , 1999 .

[15]  John M. Cioffi,et al.  A practical discrete multitone transceiver loading algorithm for data transmission over spectrally shaped channels , 1995, IEEE Trans. Commun..

[16]  Norihiko Morinaga,et al.  Adaptive modulation system with variable coding rate concatenated code for high quality multi-media communication systems , 1996, Proceedings of Vehicular Technology Conference - VTC.

[17]  L. Hanzo,et al.  Turbo-coded parallel modem techniques for personal communications , 1997, 1997 IEEE 47th Vehicular Technology Conference. Technology in Motion.

[18]  R Steele,et al.  Variable rate QAM for data transmissions over Rayleigh fading channels , 1991 .

[19]  Erik Dahlman,et al.  UMTS/IMT-2000 based on wideband CDMA , 1998, IEEE Commun. Mag..

[20]  Vincent K. N. Lau,et al.  Variable rate adaptive trellis coded QAM for high bandwidth efficiency applications in Rayleigh fading channels , 1997, VTC '98. 48th IEEE Vehicular Technology Conference. Pathway to Global Wireless Revolution (Cat. No.98CH36151).

[21]  Lajos Hanzo,et al.  Adaptive Orthogonal Frequency Division Multiplexing Schemes , 1998 .

[22]  Hikmet Sari,et al.  Transmission techniques for digital terrestrial TV broadcasting , 1995, IEEE Commun. Mag..

[23]  Lajos Hanzo,et al.  Interference aspects of adaptive modems over slow Rayleigh fading channels , 1999 .

[24]  Andrea J. Goldsmith,et al.  Adaptive coded modulation for fading channels , 1997, Proceedings of ICC'97 - International Conference on Communications.

[25]  A. Czylwik,et al.  Adaptive OFDM for wideband radio channels , 1996, Proceedings of GLOBECOM'96. 1996 IEEE Global Telecommunications Conference.

[26]  Irving Kalet,et al.  The multitone channel , 1989, IEEE Trans. Commun..

[27]  A. Glavieux,et al.  Near Shannon limit error-correcting coding and decoding: Turbo-codes. 1 , 1993, Proceedings of ICC '93 - IEEE International Conference on Communications.

[28]  A. Goldsmith,et al.  Variable-rate variable-power MQAM for fading channels , 1996, Proceedings of Vehicular Technology Conference - VTC.

[29]  B. Engstrom,et al.  A system for test of multiaccess methods based on OFDM , 1994 .

[30]  Lajos Hanzo,et al.  Burst-by-burst adaptive joint detection CDMA , 1999, 1999 IEEE 49th Vehicular Technology Conference (Cat. No.99CH36363).

[31]  Patrick Robertson,et al.  A concept of digital terrestrial television broadcasting , 1995, Wirel. Pers. Commun..

[32]  Kevin L. Baum,et al.  Adaptive antennas for OFDM , 1998, VTC '98. 48th IEEE Vehicular Technology Conference. Pathway to Global Wireless Revolution (Cat. No.98CH36151).

[33]  Lajos Hanzo,et al.  Latency and networking aspects of adaptive modems over slow indoors Rayleigh fading channels , 1999 .

[34]  Lajos Hanzo,et al.  Single- and Multi-carrier Quadrature Amplitude Modulation : Principles and Applications for Personal Communications, WLANs and Broadcasting , 2000 .