Comparison of two modulation choices for broadband wireless communications

Abstract

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 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 issues. Our simulation results allow some relevant conclusions: there is no 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 problem of MC schemes with large number of subcarriers can be mitigated (e.g. through digital clipping), but without avoiding a significant amplification 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.