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The paper describes an approach to estimate 2×2 MIMO channel capacity of a shark-fin radome antenna designed for multiple LTE bands by using channel matrices measured from drive tests in a real driving environment with a commercially available LTE radio network analyzer. The nonproduction shark-fin radome antenna that is mounted on the roof of a sedan is treated as a black box, and the estimated channel...
Recent works on massive multiple-input multiple-output (MIMO) have shown that a potential breakthrough in capacity gains can be achieved by deploying a very large number of antennas at the basestation. Although transmit-side channel state information (CSI) can be obtained by employing channel reciprocity in time division duplexing (TDD) systems, explicit feedback of CSI from the user to the basestation...
In this paper we examine convergence properties of massive MIMO systems with the aim of determining the number of antennas required for massive MIMO gains. We consider three characteristics of a channel matrix and study their asymptotic behaviour. Furthermore, we derive ZF SNR and MF SINR for a scenario of unequal receive powers. In our results we include the effects of spatial correlation. We show...
In this paper, we derive the exact expression of the finite-signal to noise ratio (SNR) diversity-multiplexing tradeoff (DMT) for Rayleigh fading multiple-input multiple-output (MIMO) channels with dual correlated antennas at the transmitter (2×Nr) and/or at the receiver (Nt ×2). We first derive the exact outage probability versus SNR. While finite-SNR DMT and outage probabilities are usually only...
This paper presents a performance model of a wireless network with one-antenna transmitter scheduling information towards a set of terminals in a time-division fashion. Each terminal is enabled with a multiple-antenna maximum ratio combining (MRC) receiver. The objective of this model is to evaluate the performance of adaptive modulation and coding (AMC) in Rayleigh fading channels under two assumptions:...
Channel frequency and spatial correlation are essential for adaptive channel prediction, which enables flexible scheduling. This correlation information is determined by the environment and can be learned and stored in a map to avoid online tracking. In this paper we propose a method to generate a channel frequency-spatial correlation map from the measurement campaign. Only two position-dependent...
Body area network considering the external areas of human body is a promising new application. In order to develop efficient body area network system, a communication channel modeling is essential. However, there are few models considering the effect of human body. This paper reports the empirical Ultra wideband(UWB) channel model for body area network. Using the frequency domain measurement system,...
We consider a multi-cell multi-user downlink channel of a time-division duplex (TDD) MIMO system, where the base stations (BSs) employ the concept of massive MIMO, i.e., they are equipped with a large number of antennas. In addition, the number of users increases with the same speed. Focusing on the practical impairments of the channel such as pilot contamination and, in particular, delayed channel...
This paper describes the design and implementation of an array system that includes a frequency domain beamformer that will coherently combine the downlinked signals from up to eight inputs at each of NASA's three Deep Space Communications Complexes (DSCC). The array signal processor digitizes inputs with an intermediate frequency (IF) bandwidth of 100 to 600 MHz, coherently combines the inputs digitally,...
Space limitation and multi-antenna channel acquisition prevent Massive multiple-input multiple-output (MIMO) from being easily deployed. The use of multi-polarized antennas can be one solution to alleviate the first obstacle. Furthermore, the dual structured precoding, in which a preprocessing based on the spatial correlation and a subsequent linear precoding based on the short-term channel state...
The optimal decentralization of multi-cell minimum power beamforming requires exchange of terms related to instantaneous inter-cell interference (ICI) values or channel state information (CSI) via a backhaul link. This limits the achievable performance in the limited backhaul capacity scenarios, especially when dealing with a fast fading scenario or a large number of users and antennas. In this work,...
Secret key generation from reciprocal multi-antenna channels is an interesting alternative to cryptographic key management in wireless systems without infrastructure access. In this work, we study the secret key rate for the basic source model with a MIMO channel. First, we derive an expression for the secret key rate under spatial correlation modelled by the Kronecker model and with spatial precoding...
A multiuser MIMO (MU-MIMO) TDD system in which the base station (BS) uses a large scale antenna array to communicate with single-antenna mobile users is considered. We present novel schemes to estimate both large-scale and small-scale fading coefficients by uplink pilot sequences. The large-scale fading coefficients (LSFCs) are usually ignored or assumed perfectly known and almost all MIMO channel...
A new RFID reader for the 13.56 MHz carrier frequency was developed in the framework of the collaboration between Freaquent Frosch Electronics (FE) and the first author. The reader is intended to cover the standards ISO/IEC FDIS 18000 [1], ISO/IEC FCD 15693 [2] and to provide long-range reading as well as inventory of large collections of tags. The reader features a class E switching power amplifier...
In the paper authors present the general idea of software correlator in e-VLBI system. The e-VLBI idea is undoubtedly the future of radio astronomy which allows accelerate both measurement and post-processing procedures. Software correlation idea is a new approach to the space observation base on very long baseline interferometry method. It significantly reduces processing time of obtained data from...
Space-polarization multiple input multiple output (SP-MIMO) communication systems can provide improved reliability, increased data rates, and higher energy efficiency as compared to conventional co-polarized MIMO (CP-MIMO) systems. To achieve these gains relative to CP-MIMO arrays, SP-MIMO architectures employ a dual-polarized (DP) antenna at each of the antenna locations, effectively doubling the...
Unlike triple-polarized antennas, dual-polarized antennas can be easily implemented into thickness limited devices and thus have received much attention recently. Dual-polarized antennas have the potential to double the channel capacity in comparison with an omnidirectional single-input single-output (SISO) system. However, in real three-dimensional (3D) scenarios, dual-polarized antennas cannot capture...
Optimal precoding in the relay with partial channel state information in the relay is studied in this paper. It is assumed that the antennas of the relay are correlated. Transmission only via the eigenvector corresponding to the largest eigenvalue of the correlation matrix is investigated in this paper which is called Largest Eigenmode Relaying (LER). We derive necessary and sufficient condition under...
A dual-element, dual-band meander-line based printed MIMO antenna system is proposed. The meander line is used to achieve resonance at low band. The antenna system resonates at the low band at 870MHz with an experimental −6dB bandwidth of 75MHz ranging from 830–905MHz. The high band resonance is achieved by a secondary arm connected to the feed line of the meander-line antenna structure. The high...
This paper introduces a novel approach to model Received Signal Strength (RSS) measurements in cellular networks for user positioning needs. The RSS measurements are simulated by constructing a synthetic statistical cellular network, based on empirical data collected from a real life network. These statistics include conventional path loss model parameters, shadowing phenomenon including spatial correlation,...
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