Implementation and Simulation of a MIMO System's Physical Layer

Abstract

The objectives of this thesis are the presentation of the fundamental notions of Multiple Input Multiple Output (MIMO) systems and the creation of models simulating their behaviour. The principal target through this process is to provide Bit-Error-Rate (BER) diagrams in order to derive conclusions about the performance of such systems, especially in comparison to typical Single Input Single Output (SISO) systems in multipath fading environments, namely to prove that the employment of more antennas leads to enhanced results. Emphasis is placed on the so called “Space-Time Block Coding” (STBC) technique, a method that affords full diversity and requires straightforward linear operations at the transmission and reception side. The software used to simulate such systems is Simulink-MATLAB. Simulink is a block diagram environment for multidomain simulation and Model-Based design. It affords the ability to model and analyze systems whose exits vary in time. Various signal modulations (BPSK, QPSK, 8PSK, 16QAM) are employed. However, before performing the simulations, a comprehensive analysis of the most significant notions and guiding principles of wireless digital communications was considered essential to be presented so as to provide the reader with the necessary knowledge and a solid grounding in MIMO communication systems. In the conclusion we discuss the future of Multiple Input Multiple Output systems and recommend alterations and further explorations that could lead to the construction of more efficient and enhanced wireless communication systems.