Duality analysis and improving the capacity of multi-input multi-output channel using dirty paper coding technique

In wireless communication, Multi-Input Multi-Output (MIMO) technology offers significant increase in data throughput and link range without additional bandwidth. The dirty paper coding (DPC) achieves the sum rate capacity of Gaussian MIMO broadcast channel. The dirty paper coding is a technique for efficient transmission of digital data through a channel that is subject to some interference that is known to the transmitter. This technique consists of precoding the data so as to cancel the effect of interference. The duality relationship between BC and MAC channel has been studied and The Sato upper bound and Marton´s inner bound on the capacity of Broadcast channel has been considered and applied this capacity to the MAC channel by showing the duality. The use of dirty paper coding closely achieves the sum-rate capacity region of broadcast channel. MIMO is abbreviation of Multiple Input Multiple Output. In MIMO fading environment, the so called degenerating channels or keyholes may exist that exhibit low partial fading correlation at both ends of the link but still have poor rank properties, and hence low ergodic capacity. The performance of dirty-paper coding over MIMO keyhole channels has been analyzed. The capacity and the probability of error of a MIMO system with Binary phase shift keying (BPSK) over keyhole channel. This paper also proves the intuitive result that the capacity under keyhole condition can be improved using Dirty paper coding.