Capacità del canale Gaussiano multi-antenna: architetture di ricevitori

WIRELESS networking constitutes an important component of future information technology applications. Multiple-input multiple-output (MIMO) is the current inclination to increase data rate in wireless networks. Channel capacity determines the amount of reliable data transmission between the transmitter and the receiver. MIMO has the advantage of reliable communication over wireless channel because of utilizing the channel capacity properly. The pioneers of this work are Winters [1987], Foschini [1996] and Teletar [1999]. We investigate the use of multiple trasmitting and/or receiving antennas for single user communicatons over the additive Gaussian channel with fast fading. We show that the potential gains of such multi-antenna system over single-antenna systems is rather large under indipendence assumptions for the fades and the noise at different receiving antennas. When the channel state information is unknown at the transmitter but is know (tracked) at the received, we investigate a codec architecture that can realize a significant portion of great capacity promised by information theory. Use (t;r) to express the number of antenna elements at the trasmitter and riceiver. An (n;n) analysis show that the n received waves interfering randomly, capacity grows linearly with n and is enormous. Among various Bell Labs layered space-time (BLAST) architectures over multiple input multiple output channels, we focus on the horizontal BLAST (H-BLAST) transmission scheme as it can achieve the channel capacity with a simple receiver, namely the successive cancellation (SIC) receiver.