BER analysis of Quasi and Rotated Quasi STBC MIMO Systems under effects of doppler shifts

Multiple-Input Multiple-Output (MIMO) has become one of the key technologies for wideband wireless communication systems. MIMO channels are mainly used to increase capacity and data rate for any wireless systems. In this paper, we exploits the space and time diversity simultaneously to improve the performance of system under quasi static mobile radio channels A general Quasi and Rotated Quasi Space-Time Block Coded (STBC) MIMO structure is presented in this paper. BER analysis is presented in terms of code rate and diversity achieved using Quasi and Rotated quasi STBC methods. Further, simulations are carried out using above two STBC methods with various modulation schemes in quasi static Jake´s channel model and then optimum coding method is suggested for 4×1 MIMO systems.