Multiple antenna systems, such as Multiple Input Multiple Output (MIMO), are an essential
part of latest standards of wireless communications such as IEEE 802.11n (Wi-Fi), 3GPP Long
Term Evolution and its advanced versions (LTE and LTE-A), WiMAX, HSPA+ and future
technologies. In these days, MIMO is deployed in many of the modern wireless routers to improve
the throughput of a wireless local area network (WLAN). The future of MIMO is to be deployed
in mobile cellular standards such as IEEE 802.16 which is known as WiMAX ,third Generation
Partnership Long Term Evolution (3GPP LTE) (3GPP and in mobile communication devices with
MIMO capabilities. The MIMO technology is important in achieving high data rates for the
demands of standards broadband and multimedia services. In this paper we have proposed a twostep channel capacity enhancement scheme where the channel capacities of a multiple antenna
System can be enhanced by some amount without using extra transmit power or spectral bandwidth.
Multiple antenna techniques can be either diversity techniques or spatial multiplexing techniques.
In this scheme, our objective is to investigate the characteristics of spatial multiplexing techniques
to improve the transmission speed. By exploiting the channel state information (CSI) and channel
matrix symmetry at both the transmitter and receiver; we can enhance the capacity of the channel.
In this scheme, we will exploit the spatial correlations between transmitter and receiver ends to
enhance the overall capacity of the MIMO channel in two steps. The first step is by decomposing
and factoring the channel matrix into independent orthogonal AWGN(Additive White Gaussian
Noise) sub channels to minimize correlation among the transmitted streams and this will facilitate
the channel capacity to be the algebraic sum of the independent orthogonal sub channels. The
problem here is it will be very difficult to practically implement it as it needs full knowledge of
the channel matrix at the side of transmitting component. This means CSI is required to be known
at the transmitting end. Since the channel matrix is merely estimated at the receiving side and
sending this information to the transmitting side would need additional resources. By estimating
the channel state, H, at the side of receiving end and feeding it to side of transmitting end at the
expense of some additional resource, we can enhance the capacity and reliability of the channel.
This is especially good approach for slowly fading channels. The second step is by configuring
transmit and receive antennas in such a way that the resulting channel matrix would be symmetrical
and well-conditioned channel where the matrix whose elements in opposite pairings about the
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matrix’s diagonal elements are equal. This arrangement results in enhanced channel capacity and
reliability as the decomposed channel matrix will tend have full rank.
Finally, the performance of our scheme is evaluated in Matlab simulation environments using
Monte Carlo simulation mechanisms for different scenarios. The simulation results show that a
significant improvement in performance of channel capacity enhancement can be brought about at
the expense some additional resources and system complexity.