Performance of adaptive transmit diversity with orthogonal space-time block coding in microcell and macrocell channel environments

Recently an adaptive transmit eigenbeamforming with orthogonal space-time block coding (Eigen-OSTBC) has been proposed. This model was simulated over macrocell environment with a uniform linear array (ULA) at the base station (BS). In this paper we investigate the impact of various antenna geometries on the performance of this scheme as well as the performance over microcell and macrocell channel environments. The geometrical-based hyperbolically distributed scatterers (GB-HDS) channel models were simulated with angular spreads (AS) taken from experimental data. The ULA and the uniform circular array (UCA) are considered at the BS. In the simulation conducted, results have shown that the Eigen-OSTBC system has a higher performance gain than OSTBC systems in macrocell than microcell environment (where the AS gets larger). It is also observed that BS antenna array with different separation distances also affects the performance of both Eigen-OSTBC and OSTBC systems. However, the error-rate performance curves of ULA and UCA configurations are very similar.