Optimised Pilot Pattern for Dynamic Spectrum Access Multicarrier Systems

Optimal training design for wireless multicarrier communication systems has recently become an active research area. However, the existing solutions are not applicable to dynamic spectrum access systems as they do not take into account the restrictions on pilot subcarrier placement or the interference impact on the channel estimation performance. In such a case the problem of optimal pilot-assisted multicarrier transmission has to be reformulated, taking into account deactivated subcarriers and second-order interference statistics. In this paper, we propose an adaptive algorithm to construct a suboptimal pilot pattern, which minimises channel estimation error variance and can incorporate any restrictions on the transmit subcarriers.