Design, Simulation & Concept Verification of 4 × 4, 8 × 8 MIMO With ZF, MMSE and BF Detection Schemes

In a MIMO system, all the signals received excluding the one from the desired transmit antenna, are treated as interference. To get a good quality signal at the receiver these interferences must be minimized or nullified (if possible). This work focuses on studying signal detection using three different equalization techniques, namely: Zero Forcing (ZF), Minimum Mean Square Error (MMSE) and Beam Forming (BF), for a 4x4 MIMO-system. Results show that ZF equalization is the simplest technique for signal detection, However, Beam Forming (BF) gives better Bit Error Rate (BER) performances at high Signal to Noise Ratio (SNR) values with some complexity in design. For more antennas at the base station, it is too complex to design the weight matrix for ZF. However, it is suitable for BF with the help of good quality digital signal processors. Performance of MIMO- system, with 8 antennas at the base station using BF equalization, is analyzed to get BER values at different SNR. Results show a considerable improvement in BER for 8 antennas at the base station. The Study is performed with an assumption that antennas used at base station are not correlated