We propose a novel low-resolution-aware recursive least squares channel estimation algorithm for uplink multiuser multiple-input multiple-output systems. In order to reduce the energy consumption, 1-bit ADCs are used on each receive antenna. The loss of performance can be recovered by the largescale antenna arrays at the receiver. The proposed adaptive channel estimator can mitigate the distort...

In this paper, the performance of multiuser MIMO ESDM systems in downlink transmission is evaluated in both uncorrelated and correlated time-varying fading environments. In the ideal case, using the block diagonalization scheme, inter-user interference can be completely eliminated at each user; and using the E-SDM technique for each user, optimal resource allocation can be achieved, and spatial...

A novel multiuser code division multiple access (CDMA) receiver based on genetic algorithms is considered, which jointly estimates the transmitted symbols and fading channel coefficients of all the users. Using exhaustive search, the maximum likelihood (ML) receiver in synchronous CDMA systems has a computational complexity that is exponentially increasing with the number of users and, hence, i...

In a multiuser broadcast channel with M antennas at the base station and K ≥ M i.i.d. users, multiuser diversity can be exploited by optimally choosing a set of M users to serve simultaneously with linear beamforming. In order to perform the user selection, the base station requires channel state information (CSI) of all K users which is obtained through limited feedback in frequency division d...

This thesis deals with multiuser multicarrier communications over unknown time and frequency selective fading channels. Since there is a growing demand for capacity, especially in mobile communications, wireless multiuser communications experiences increasing interest in recent year. The wireless channel in general is a time and frequency selective fading channel. In that case, orthogonal frequ...

In this paper, we endeavour to seek a fundamental understanding of the potentials and limitations of training-based multiuser multiple-input multiple-output (MIMO) systems. In a multiuser MIMO system, users are geographically separated. So, the near-far effect plays an indispensable role in channel fading. The existing optimal training design for convenitional MIMO does not take the near-far ef...

This paper considers an uplink multiuser massive multiple-input multiple-output (MIMO) system with lowresolution analog-to-digital converters (ADCs), in which K users with a single-antenna communicate with one base station (BS) with Nr antennas. In this system, we present a novel multiuser MIMO detection framework that is inspired by coding theory. The key idea of the proposed framework is to c...

This paper presents a semi-blind algorithm for multiuser interference cancellation and fading amplitude estimation for downlink MIMO DS-CDMA systems with multipath fading channels. Taking advantage of the space-time information of the parametric multipath channel, the proposed algorithm first uses a space-time channel decoupler to suppress multiuser interference and then decomposes the channel ...

In this paper, novel structures for dynamic removal of multiuser interference are proposed. The natural gradient (NG) is used either to compute whitening matrices in linear blind minimum MSE or to develop new structures. As a result, we propose a family of centralized and non-centralized multiuser detectors (MUD’s). The NG provides the MUD’s with the equivariant and superfficiency properties, m...