The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
In this paper we focus on waveform coefficient matrix (WCEM) design to perform matched beampattern design with lower sidelobe level for generalized MIMO configurations. First, the relationship between transmit waveforms and beam-pattern, and the limitation of conventional waveform covariance matrix (WCVM) design are briefly discussed. Then a power approximation method (PAM) by minimizing both integrated...
In this paper, multiuser multiple-antenna (MUMIMO) relay networks employing opportunistic scheduling and operating in the presence of rayleigh fading and co-channel interference are analyzed Notwithstanding the system complexity, due to the newly found complementary moment generating function transform (CMGF) operator, an exact expression for the capacity under general conditions is obtained. Moreover,...
In massive multiple-input multiple-output (MIMO) systems, linear minimum mean square error (MMSE) detection is near-optimal but involves large dimensional matrix inversion, which results in high complexity. To this end, Neumann series expansion (NSE) approximation, which avoids the direct computation of the matrix inversion, is recently investigated due to its low implementation complexity. Unfortunately,...
A multi-pair large-scale multi-antenna relaying system is considered in this paper. We investigate the energy efficiency (EE) performance by taking the circuit power consumption into account when maximum ratio combining/maximum ratio transmission is explored at the relay station (RS). By utilizing the law of large numbers, an analytical expression of EE is derived. Based on this, we characterize the...
We consider the downlink multi-user multi-cell massive MIMO systems, and our system model accounts for channel estimation, pilot contamination, and uniformly random user location distribution. An equivalent channel model is investigated which indicates that the users in various cells come through the same ‘fast fading’ when they reuse the same training signal in uplink pilot transmission phase. Assuming...
Full-duplex multiple-input-multiple-output (MIMO) relaying is capable of providing coverage for remote users with low power consumption, by exploiting the spatial dimensions of MIMO to suppress different types of interference, including self interference (SI) and multi-user interference (MUI). In a general network with multiple full-duplex MIMO relays, inter-relay interference (IRI) emerges and degrades...
We present a reconfigurable GPU-based uplink detector for massive MIMO software-defined radio (SDR) systems. To enable high throughput, we implement a configurable linear minimum mean square error (MMSE) soft-output detector and reduce the complexity without sacrificing its error-rate performance. To take full advantage of the GPU computing resources, we exploit the algorithm's inherent parallelism...
This paper proposes a novel three-dimensional (3D) cylinder geometry-based stochastic model (GBSM) for non-isotropic multiple-input multiple-output (MIMO) Rice fading channels in high-speed train (HST) wireless communications under deep cutting scenarios. Using a validated approximation, the closed-form expression of the space-time correlation function (ST CF) of the proposed GBSM is obtained. Different...
Recently a systematic method was presented for the generation of whole families of “Fixed Point Transformations” that can be used in nonlinear adaptive control of “Single Input - Single Output (SISO)” systems as alternatives of Lyapunov's “direct method”. In the present paper further development of this alternative method is considered. It consists in the generalization of the method for “Multiple...
Massive Multiple-Input Multiple-Output (MIMO) is foreseen to be one of the main technology components in next generation cellular communications (5G). In this paper, fundamental limits on the performance of downlink massive MIMO systems are investigated by means of simulations and analytical analysis. Signal-to-noise-and-interference ratio (SINR) and sum rate for a single-cell scenario multi-user...
In the paper a method of synthesis of a neural controller which goal is to reduce effects of coupling of the nonlinear multi-input multi-output (MIMO) plant inputs and outputs is presented. The designed neural controller contains a set of neural nets that determine values of parameters of linear decoupling controllers calculated for the adopted nonlinear plant model at its operating points. A known...
Within the framework of Monte Carlo simulation, this paper derives a Markov chain Monte Carlo (MCMC) algorithm for efficient detection in multiple-input multiple-output (MIMO) systems using the non-orthogonal multi-carrier waveform termed generalized frequency division multiplexing (GFDM). The proposed MCMC algorithm performs the detection task in frequency domain. Its adopted proposal distribution...
Complex Wishart matrices represent a class of random matrices exploited in a number of wireless communication problems. This paper analyzes the first and second order statistical moments of complex Wishart matrices' minors. This enables to derive new closed-form approximations for the outage capacity of multiple input multiple output (MIMO) systems operating in Rayleigh fading channels at any signal-to-noise...
We consider a decentralized multisensor estimation problem where L sensor nodes observe noisy versions of a possibly correlated random source. The sensors amplify and forward their observations over a fading coherent multiple access channel (MAC) to a fusion center (FC). The FC is equipped with a large array of N antennas, and adopts a minimum mean square error (MMSE) approach for estimating the source...
Designing iterative algorithms for interference alignment (IA) is very useful for both practical and theoretical purposes. However, the existing works on iterative IA algorithms have not reported significant gains in terms of the DoF (Degrees of Freedom) over simple orthogonalization schemes. In this paper, we aim to design an iterative IA algorithm that can achieve high DoF. We recast the problem...
In this paper, we consider the uplink in a single cell multi-user massive multiple-input-multiple-output (MIMO) system, where the multi-antenna base station (BS) serves single-antenna users. The BS is equipped with three directional linear antenna arrays, each covering one-third of the cell area. We focus on one antenna array and the corresponding sector. The users are randomly placed in the sector...
In this paper, a sectorized multi-cell massive multiple-input multiple-output (MIMO) system is considered with a spatially correlated channel model. Since sum-throughput per cell is an important index for evaluating a multi-cell system, we derive the ergodic achievable uplink sum-throughput per cell of the sectorized system and give the deterministic approximation of it based on the large random matrix...
Relay selection strategies help to improve spectral and energy efficiencies, to enhance transmission robustness, or to reduce latency in cooperative networks. A novel relay selection strategy, which maximizes the overall achievable sum rate, is proposed and analyzed for multiple-input multiple-output (MIMO) amplify-and-forward two-way relay networks with spatial multiplexing. Interestingly, this strategy...
In this paper, we use stochastic geometry to characterize spatially distributed multi-antenna users within a cell that consists of a single multiple-input multiple-output (MIMO) base station (BS) equipped with a large antenna array. We also use large dimensional random matrix theory (RMT) to achieve deterministic approximations of the sum rate of this system. In particular, we consider the users inside...
The Diversity-Multiplexing Tradeoff (DMT) is studied for the large Rayleigh product channel at non-asymptotic SNRs. The first result is that, as matrix dimensions growing to infinity, the channel capacity converges to a Gaussian random variable. Based on this, we derive a compact expression for the finite-SNR DMT. From the analytical and numerical results, we gain useful insight into the fundamental...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.