Deep Fading Effect On an Individual Link of 4× 4 Mimo Communication Systems

Abstract

The hottest issue of next generation communication systems is data throughput improvement for any wireless channel conditions. Mul-ti-Input Multi-Output (MIMO) systems are the key technology for the next generation communication systems. Bill Lab Layered Space Time (BLAST) system achieves high data rates with acceptable BER performance over a good channels state. However, when the wireless channel has a considerable fading then the performance will be decreased and at a deep-fading state the system may fail to transmit any signal. This paper studies and compares the conventional 4 4 Vertical BLAST system capacity and bit error rate (BER) performance at Maximum Likelihood (ML) receiver through a simulation. It also studies the effect of a transmit link deep-fading on the effective signal to noise ratio, system BER and system capacity in 4 4 VBLAST system in a comparative way with the conventional 4 4, 3 4, 2 4 and 1 4 VBLAST system. Considering that every possible case of transmit link deep fade lower than-20dB fading gain is equivalent to switching off this transmit link and