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This paper proposes a three-dimensional (3-D) multiuser channel model for stratospheric multipath-fading channel. The birth-death process is used to model the non-stationary properties that scatterers “appear” and “disappear” on the array axes. The spatial correlation of multiuser High Altitude Platform (HAP) multiple-input multiple-output (MIMO) channel is investigated in this paper. This model can...
One of the research activities in 5G communication systems is the extension of the MIMO processing from the 2D to the 3D plane by exploiting the elevation dimension which gives an additional degree of freedom to meet the high capacity demands. Despite the growing researches concerning 3D space propagation, there are few studies that evaluate the impact of 3D propagation on MIMO performance at the...
With some recent developments in the field of wireless communication at rapid pace, users are getting a number of applications which require the precious bandwidth to work on. As the bandwidth is limited, the available spectrum is being congested day by day. Cognitive Radio System (CRS) plays an important role in such scenario. It dynamically adapts its parameters and protocols to provide unused spaces...
This paper analyzes the temporal correlation properties of mobile-to-mobile (M2M) channels, based on an extensive measurement campaign carried out in an indoor environment at 2.48 GHz. In order to model the dynamic channel characteristics, short- and long-term fading behaviors are extracted. The auto-correlation function (ACF) is characterized for different types of pedestrian movements. Finally the...
This paper analyzes the performance of full-duplex relaying (FDR) with multiple-antenna amplify-and-forward (AF) relay. The system performance due to practical wireless transmission impairments of spatial fading correlation and imperfect channel state information (CSI) is investigated. To this end, new exact closed-form expressions for the outage probability are derived, where the case of arbitrary,...
The European Space Agency mission Soil Moisture and Ocean Salinity (SMOS) is devoted, since its launch in 2009, to provide global soil moisture and sea surface salinity values. SMOS uses an L band 2-D interferometric radiometer by aperture synthesis to obtain polarimetric brightness temperature images. This work is devoted to compute the spatial correlations in the measured antenna brightness temperature...
Computationally efficient design optimization of antenna structures can be realized using variable-fidelity EM simulations, where most of the operations are performed at the level of a coarse-discretization EM model (referred to as the low-fidelity model) with occasional reference to the high-fidelity one, for the sake of model correction and design verification. An important issue is an appropriate...
This paper presents a comparison of different three dimensional (3D) MIMO Over-The-Air (OTA) multi-probe configurations. Spatial correlation is used as metric to evaluate the setup accuracy, considering different antenna probes emplacements and Elevation Spread (ES). Simulation results are presented in uniform and single cluster channel models for spherical and cylindrical 3D OTA.
MIMO technology enables high-data rates in wireless devices to allow from speech and video calls up to streaming media and web browsing all over a common platform. MIMO technology needs M antennas both in transmission and reception. Since the space in a wireless device is limited, including M antennas is a challenge. To face such challenge, two MIMO systems are proposed. A first one using a multiband...
In this paper, experimental results are presented for an encrypted wireless link between two body-worn sensor nodes fully integrated onto textile antenna platforms. Wireless communication between two persons walking in an indoor environment occurs over a unique physical propagation channel. For the purpose of data encryption, channel measurements are performed at both sides of the link, providing...
Introduction Multiple-Input-Multiple-Output(MIMO) and Multi-User MIMO (MU-MIMO) systems have been expected to improve the channel capacity over a limited bandwidth of existing networks [1], [2]. The effects on channel capacity of Single-User MIMO (SU-MIMO) systems in urban scenarios have been previously studied [3]. It has been clarified that the larger number of antennas cannot contribute the improvement...
Two techniques of non-parametric change point detection are applied to two different neuroscience datasets. In the first dataset, we show how the multivariate non-parametric change point detection can precisely estimate reaction times to input stimulation in the olfactory system using joint information of spike trains from several neurons. In the second example, we propose to analyze communication...
A Minkowski fractal shape patch antenna covering terrestrial wireless services is presented for multiple-input-multiple-output implementation. The proposed structure is minimized upto two iteration operated at 10GHz. The end to end separation between the two antennas is 4.9mm The existence of surface waves is reduced using two inverted T and slot structure respectively, which is etched in between...
The Theory of Characteristic Modes (CM) provides a powerful tool of analyzing the radiators, which exhibits the orthogonality of basis radiation patterns. The properties of CM can be exploited by eigenvalues and eigenvectors solved by the general eigenvalue equation formulated from the Method of Moments impedance matrix. So the CM is parameterized by frequency, the tracking of which can reveal the...
Spectrum sensing presents a substantial challenge in the novel emerging telecommunications technologies, and a crucial step that should be performed by cognitive user to identify the unoccupied frequency bands, in order to enhance the spectral efficiency and the QoS to both licensed and unlicensed users. In this paper, we propose a novel sensing approach based on the cross-correlated moments' selection...
The ubiquity of computers and increasing Internet connectivity is leading to the emergence of innovative ways of learning such that terms like mixed-ability teaching, independent and flexible learning and interactive lessons are becoming buzzwords for the learning society. The availability of the enormous variety of online free resources poses problems when it comes to picking out the relevant, updated...
Time reversal (TR) technique has been announced as a promising solution for future wireless communication owing to its competency to provide lower computational complexity and higher throughput for the communication system. TR can exhibit remarkable performance especially in ultra-wideband (UWB) system. In this letter, we theoretically analysis the performance of a MIMO-OFDM system combined with the...
In this paper, we have analyzed the spatial correlation statistics of different antenna polarization setups for uniform linear and circular antenna arrays. We have compared correlation statistics of different MIMO orders. We are motivated to understand pair-by-pair correlation behavior of MIMO channel as it plays a vital role in defining the channel spectral efficiency. We have further evaluated the...
The multi-probe anechoic chamber method is promising for OTA testing. The reason can be attributed to its potential for enabling evaluating MIMO terminals in realistic environments. The focus of the paper is on investigating how to create desired spatial channel models with the multi-probe anechoic chamber setups. Simulation results have shown that with the discussed methods, the number of probes...
This paper presents a performance model of the reception process in a wireless link with one antenna transmitter and a multiple-antenna maximum-ratio combining (MRC) receiver. The objective is to address the performance evaluation of multiple antenna systems enabled with adaptive modulation and coding (AMC). Two main assumptions are used: 1) Rayleigh fading correlated channels, and 2) imperfect (outdated)...
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