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Abstract-In this article, the authors focus on a correlated channel model for secure relay beamforming in the relayeavesdropper network. In this network, a single-antenna sourcedestination pair transmits secure information with the help of a amplify-and-forward (AF) relay equipped with multiple antennas. The relay cannot obtain the instantaneous channel state information (CSI) of the eavesdropper...
This paper investigates the impact of antenna correlation on wireless powered dual-hop multi-antenna relaying systems with instantaneous channel state information (CSI) or statistical CSI at the relay. Considering the power-splitting architecture, we study the outage probability as well as the achievable diversity order of the system for amplify-and-forward protocol. Our results show that, antenna...
The method of key sharing between a mobile unit and a base station through a wireless MIMO-based fading channel is investigated. The description of a key distribution protocol is given. The expression to estimate the correct key bit agreement based on the use of guard interval is proved. Statistical properties of the key string are tested using the NIST criteria. Impossibility of key string eavesdropping...
Accurate channel state information (CSI) at transmitter is of importance to sufficiently exploit the merits of massive multiple input multiple output (MIMO). Because of the large amount of antennas at base station (BS), the pilot overhead becomes unaffordable, especially in frequency-division duplexing (FDD) massive MIMO systems. To alleviate the overwhelming pilot overhead, a novel channel estimation...
This paper describes a 28nm fully integrated 79 GHz Phase Modulated radar SoC including 2TX, 2RX and the mm-wave frequency generation. A custom digital core generates the pseudo random sequence and performs correlation and accumulation of the digitized received data. With 1W power consumption, 7.5 cm range resolution is achieved while antennas arrangement allows for 5° resolution over ±60° elevation...
This paper evaluates the simultaneous impact of antenna correlation and imperfect channel state information (CSI) on the sum rate achievable in the compound multiple-input multiple-output (MIMO) Broadcast Channel (BC). The considered correlation model incorporates the correlation due to the proximity of antenna elements at both transmitter and receiver sides. We analyse the achievable sum rate and...
In this paper, we introduce the concept of Twin-Antenna system for Energy Sensing and Low-Noise blind deconvolution using Field-Field Correlations. The holographic principle seen as a bridging connection between the geometry and information content of space-time is introduced for exploiting the Covariant Entropy bound. The Entropy-to-Energy and Entropy-to-Surface-Area bounds open new possibilities...
The aim of this paper is to propose optimization techniques for source stirred reverberation chambers. In particular, the stirring function is accomplished by 62 monopole antennas distributed on the chamber walls, and subsequently fed two at a time for a total of 1891 combinations. At first it is shown how an irregular placement of the antenna increases the chamber performances. Subsequently, an optimization...
In this paper, a non-stationary geometry-based stochastic model (GBSM) for high-speed train (HST) MIMO channels is proposed. The proposed model employs geometry-based elliptical scattering model, where the received signal is a superposition of line-of-sight (LOS) and single- bounced rays. The time-varying reference system is introduced to more accurately characterize the non-stationarity of HST MIMO...
Algorithms based on signal correlation have low computational complexity and require little knowledge on primary signals or noise signals. However, their detection performance becomes relatively terrible in low signal-to-noise ratio (SNR) regime with weak signal correlation, which happens to be quite common in practical systems. In this paper, a weighted blind spectrum sensing algorithm based on signal...
Massive multiple-input multiple-output (MIMO) is a key technology driving the 5G evolution. It relies on the use a large number of antennas at the base-station to improve network performance. The performance of massive MIMO systems is often limited by imperfect channel estimation because of pilot contamination. Recently, several channel estimation techniques have been proposed to minimize the performance...
By taking the imperfect channel state information(CSI) into account, the optimal precoding matrix is deduced with the proposition that the full CSI of the source-relay link and the estimation errors and antennas correlation information of the relay-destination link are known by the relay node. Considering the maximum power constraint at the relay node, the precoding matrix is optimized based on the...
The Soil Moisture and Ocean Salinity (SMOS) mission by the European Space Agency (ESA) was launched in 2009 [1]. Since then, it has produced a continuous stream of valuable geophysical data over land, ice and ocean [2] However, a problem which does persist is the so-called land-sea contamination (LSC) effect, an artificial increase of brightness temperature around large land masses that enters into...
In diversity-based multiple antenna cognitive radio system, the performance of the existing cooperative spectrum sensing algorithms based on covariance matrix degrades seriously due to the channel correlation. In this paper, we formulate spectrum sensing as a multinomial distribution test problem, and then apply the Discrete Anderson Darling (DAD) test, one of discrete goodness of fit tests, to examining...
Ground-based and shipborne Communications ESM systems operating in the VHF and UHF bands have been typically based on arrays designed accordingly to regular geometries. Prominent example are Uniform Circular Arrays (UCAs). Unfortunately, UCAs are not easily installable on small or narrow platforms, as it is in the case of UAVs; this is due also to the long wavelengths of the signals in the VHF band...
In this paper, a method to calculate the correlation coefficient for four antenna elements that have parallel RLC equivalent circuit is presented. The method is simpler than using the 3D far field pattern method and also more reliable and accurate than using the S-parameters method. It only requires the S-parameters and the radiation efficiency and gives good estimation of the correlation coefficient...
A dedicated stochastic framework to address the impact of substrate compression on the performance of textile antennas is presented. The joint probability distribution of the height and the permittivity of a compressible substrate is experimentally estimated. Then, a generalized polynomial chaos technique accurately quantifies the effect of the random variations on both substrate parameters on the...
A three-dimensional (3D) channel model for multiple-input multiple-output (MIMO) mobile communication system including field patterns of mutually uncoupled separated antennas is proposed. The model utilizes both geometrical and stochastic properties of propagation environment to describe fading correlation and simulate channel coefficients behavior over space and time. This approach gives more degrees...
Site diversity method has been used to mitigate the effect of rain attenuation since the beginning of satellite communication era. A distance in site diversity method is designed as short as possible to avoid the effect of rain attenuation at the same time. To achieve more accuracy and reliability in the site diversity design, we propose the spatial correlation factor evaluated from rain gauge network...
This paper discusses multi-probe anechoic chamber setups for evaluating MIMO capable terminals with emphasis on generating spatial channel models. The multi-probe anechoic chamber method is a promising method for over the air testing. The reason can be attributed to its potential for enabling evaluating MIMO terminals in realistic propagation environments. The focus of the paper is on investigating...
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