This letter addresses the problem of robust transceiver design for the multiuser multiple-input-multiple-output (MIMO) downlink where the channel state information at the base station (BS) is imperfect. A stochastic approach which minimizes the expectation of the total mean square error (MSE) of the downlink conditioned on the channel estimates under a total transmit power constraint is adopted...

In a two-user broadcast channel where one user has full CSIR and the other has none, a recent result showed that TDMA is strictly suboptimal and a product superposition requiring non-coherent signaling achieves DoF gains under many antenna configurations. This work introduces product superposition in the domain of coherent signaling with pilots, demonstrates the advantages of product superposit...

In this paper, the efficient channel estimation and equalization techniques for a high-rate multi-input multi-output orthogonal frequency division multiplexing (MIMO-OFDM) system is implemented. In particular the article presents the implementation of MLD along with Alamauti receiver technique for implementation of MIMOOFDM. Finally, we evaluate the BLER and BER for the proposed schemes by comp...

In the downlink of a multiuser multiple-input multiple-output (MIMO) communication system, simultaneous transmission to several users requires joint optimization of the transmitted signals. Allowing all users to have multiple antennas adds an additional degree of complexity to the problem. In this paper, we examine the case where a single base station transmits tomultiple users using linear pro...

In this paper, an efficient scheduling technique for multiuser MIMO downlink with block diagonalization precoding in millimeter waves channel is presented. The scheduling technique is based on employing hybrid DE/EPSO optimization method to maximize the sum rate capacity for selected number of users for outdoor cellular systems. The proposed scheduling scheme achieves almost similar capacity pe...

In this paper, to improve the energy efficiency (EE) of multi-user multiple-input multiple-output (MIMO) orthogonal frequency-division multiple access (OFDMA) system, an Energy-efficient multiple access (EMA) scheme is proposed. It improves EE by selecting either time-division multiple access (TDMA) or space-division multiple access (SDMA) based on the no. of users or power consumption. Here, w...

Downlink of a multiuser MIMO system is considered, in which the base station (BS) and the user terminals are both equipped with multiple antennas. Efficient transmission schemes based on zero-forcing (ZF) linear receiver processing, eigenmode transmission, and partial channel state information (CSI) at the BS transmitter are proposed. The proposed schemes utilize a handshaking procedure between...

Future cellular systems based on the use of millimeter waves will heavily rely on the use of antenna arrays both at the transmitter and at the receiver. For complexity reasons and energy consumption issues, fully digital precoding and postcoding structures may turn out to be unfeasible, and thus suboptimal structures, making use of simplified hardware and a limited number of RF chains, have bee...

The multi-carrier code division multiple access (MCCDMA) is a strong candidate to facilitate multi-user (MU) multi input multi output (MIMO) communication for the current and next generation wireless mobile system. An orthogonal frequency division multiplexing (OFDM) based MCCDMA system with limited feedback channel is considered for reducing channel state information (CSI) feedback load. The r...

in this paper the problem of minimizing the total transmitting power subject to a fixedtotal bit rate in ofdm systems is considered. upper bounds on transmitting power and bit rate ofeach subcarrier can also be taken into account. in practice, the number of bits of each subcarriershould be integer and nonnegative. in this paper an analytical optimal solution is derived for thecase of assuming t...