Comparison of two modulation choices for broadband wireless communications

Both single-carrier (SC) and multicarrier (MC) modulation schemes are currently recommended for broadband wireless communications. MC schemes are known to be very robust against severe time dispersion effects of multipath propagation, without requiring complex receiver implementations, while SC schemes are supposed to suffer from an "equalization disadvantage", when compared with their MC counterparts, under such highly dispersive conditions. This paper provides an overall comparison of these modulation choices, by considering a similar frequency-domain equalization in both cases, and then by adding the impact of channel coding and amplification issues. Our simulation results allow some relevant conclusions: there is no "equalization advantage" for the MC side; under the MC choice we can compensate for the worse uncoded transmission performance, provided that the code rate is low enough; the well-known power amplification problem of MC schemes with large number of subcarriers can be mitigated (e.g. through digital clipping), but without avoiding a significant "amplification advantage" for the SC side. The overall performance advantage of selected SC schemes is clear from our results, which are especially significant since the required implementation complexity and power consumption are not higher than with the MC choice.

[1]  G. Kadel,et al.  Diversity and equalization in frequency domain a robust and flexible receiver technology for broadband mobile communication systems , 1997, 1997 IEEE 47th Vehicular Technology Conference. Technology in Motion.

[2]  D. Graupe,et al.  Punctured Convolutional Codes of Rate (n - 1)/n and Simplified Maximum Likelihood Decoding , 1979 .

[3]  J. Bibb Cain,et al.  Punctured convolutional codes of rate (n-1)/n and simplified maximum likelihood decoding (Corresp.) , 1979, IEEE Trans. Inf. Theory.

[4]  R. Dinis,et al.  On the performance evaluation of OFDM transmission using clipping techniques , 1999, Gateway to 21st Century Communications Village. VTC 1999-Fall. IEEE VTS 50th Vehicular Technology Conference (Cat. No.99CH36324).

[5]  H. Rohling,et al.  Multi-carrier spread spectrum and its relationship to single-carrier transmission , 1998, VTC '98. 48th IEEE Vehicular Technology Conference. Pathway to Global Wireless Revolution (Cat. No.98CH36151).

[6]  Martin V. Clark.  Adaptive frequency-domain equalization and diversity combining for broadband wireless communications , 1998, IEEE J. Sel. Areas Commun..

[7]  P. Schramm,et al.  Modulation for HIPERLAN type 2 , 1999, 1999 IEEE 49th Vehicular Technology Conference (Cat. No.99CH36363).

[8]  Hikmet Sari,et al.  An analysis of orthogonal frequency-division multiplexing for mobile radio applications , 1994, Proceedings of IEEE Vehicular Technology Conference (VTC).

[9]  Xiaodong Li,et al.  Effects of clipping and filtering on the performance of OFDM , 1998, IEEE Communications Letters.

[10]  A. Czylwik.  Synchronization for single carrier modulation with frequency domain equalization , 1998, VTC '98. 48th IEEE Vehicular Technology Conference. Pathway to Global Wireless Revolution (Cat. No.98CH36151).

[11]  António Gusmão,et al.  A Novel Approach to Modeling of OQPSK-Type Digital Transmission over Nonlinear Radio Channels , 1997, IEEE J. Sel. Areas Commun..

[12]  Burton R. Saltzberg,et al.  Intersymbol interference error bounds with application to ideal bandlimited signaling , 1968, IEEE Trans. Inf. Theory.

[13]  B. Daneshrad,et al.  Equalized GMSK, equalized QPSK and OFDM, a comparative study for high-speed wireless indoor data communications , 1999, 1999 IEEE 49th Vehicular Technology Conference (Cat. No.99CH36363).