Pilot-assistant subcarrier allocation in virtual MISO-OFDM system

For virtual multiple-input-single-output (MISO) orthogonal frequency division multiplexing (OFDM) system, efficient resource allocation is required to provide high transmission throughput. This paper proposes two adaptive pilot-assistant subcarrier allocation schemes - the 1^st scheme assumes the cluster head as receiving node (S1), and the 2^nd introduces a contention process to choose the best receiving node (S2). Both S1 and S2 allocate a subcarrier to transmitting node with the highest magnitude of channel frequency response on this subcarrier. And if the subcarrier is in deep fade for all transmitting nodes, it is not used to avoid burst error. Numerical simulations demonstrate that two proposed schemes outperform the fixed subcarrier allocation schemes in the aspects of bit error rate (BER) and spectral efficiency (SE). Compared with S1, S2 is better at BER and SE, but worse at delay and complexity. Both S1 and S2 have low computation complexity, and are easy to implement.