Novel transmit diversity approach combining SFBC and CDD in LTE-Advanced system

This paper addresses a novel open-loop transmit diversity transmission scheme combining space-frequency block coding with cyclic delay diversity for MIMO-OFDM systems, particularly for the downlink of LTE-Advanced system to exploit full diversity freeing of adding extra overhead of pilot sequence, which is anticipated widely deployed in the near future. The combination of SFBC and CDD is able to introduce additional time diversity and hence significant gains from the spatial, frequency, time diversity gains can be efficiently exploited associated with it. Furthermore, for eight transmit antenna case, numerical simulation results under different modulation modes and coding rates scenarios are given to show that the proposed scheme outperforms previous schemes such as pure quasi-orthogonal space-frequency coded OFDM (QO-SFBC) and CDD scheme in terms of block error rate (BLER) and therefore the new scheme enables transmission reliability and coverage without significantly increasing system complexity.