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To enable realistic studies of massive multiple-input multiple-output systems, the COST 2100 channel model is extended based on measurements. First, the concept of a base station-side visibility region (BS-VR) is proposed to model the appearance and disappearance of clusters when using a physically-large array. We find that BS-VR lifetimes are exponentially distributed, and that the number of BS-V

We present recent results on spatially coupled turbolike codes and point out a connection to the self-concatenatedtrellis construction proposed by Loeliger in 1997 [1].

Problem: Refugee entrepreneurship has recently garnered a growing academic and political interest around the world. The rate of scientific publication has soared in the last few years due to the scholarly urgency on the topic following the ‘global refugee crises’. Nevertheless, the research field is currently underdeveloped with existing knowledge dispersed across various and often disconnected di

This paper proposes a pragmatic methodology to characterize mutual coupling in uniform linear arrays (ULAs). The classical coupling model used in the literature of multiple input multiple output (MIMO) antenna arrays is based on impedance parameters, resulting valid only for electromagnetically small antennas, e.g. short dipole. To test the robustness and accuracy of the proposed coupling model we

Massive multiple-input multiple-output (MIMO) has gained a tremendous amount of attention as a key enabler of fifth-generation cellular systems. The majority of the vast literature on massive MIMO is based on fully digital processing, where each antenna element in the massive array is equipped with an up/down-conversion chain. Unlike previous works, we present a suite of greedy algorithms using pu

Favorable propagation (FP) and channel hardening (CH) are desired properties in massive multiple-input multiple-output (MIMO) systems. To date, these properties have primarily been analyzed for classical statistical channel models, or ray-based models with very specific angular parameters and distributions. This paper presents a thorough mathematical analysis of the asymptotic system behavior for

Multiple-input multiple-output (MIMO) over-the-air (OTA) testing is a standardized procedure to evaluate the performance of MIMO-capable devices such as mobile phones and laptops. With the growth of the vehicle-to-everything (V2X) service, the need for vehicular communication testing is expected to increase significantly. The so-called multi-probe anechoic chamber (MPAC) setup is standardized for

Multiple-input multiple-out (MIMO) is a mature technology in modern wireless communications. However, it is challenging to implement multi-antennas for MIMO operation in compact mobile terminals, due to high mutual coupling and correlation among closely spaced antenna elements. Moreover, a conventional terminal chassis only offers one resonant mode below 1 GHz, complicating multi-antenna design. R

A low-cost microstrip patch antenna array is proposed in this paper for automotive radar applications in ISM 24 GHz band. The elements of the center-fed array are connected in series to make a compact design with low complexity by obviating Wilkinson power divider. This approach also helps to reduce the dielectric losses of the array. A full-wave electromagnetics (EM) software EMPIRE XPU is used i

It is known that the fundamental radiation mode of a mobile terminal chassis enables wideband coverage below 1 GHz. However, in theory, the bandwidth of this chassis mode extends infinitely beyond 1 GHz. In this paper, we investigate the use of inductive coupling element (ICE) to significantly increase the antenna bandwidth obtainable from the fundamental mode. Using characteristic mode analysis,

A channel sounder is an advanced measurement system to estimate the behavior of wireless propagation channels. In this paper, we present the antenna array design for a 28GHz massive multiple-input multiple-output system, capable of measuring 256×128 dual-polarized channels, including dynamic properties of angular, delay, Doppler, and polarization parameters, respectively. Unique in comparison to o

Background: For a significant proportion of the older population, increasing age is associated with health problems and worsening health. Older family caregivers are largely responsible for care of next-of-kin living at home, which impacts their own physical and mental health both positively and negatively. However, evidence is insufficient regarding the health situation of older caregivers. The a

Vehicle-to-vehicle (V2V) wireless communications can improve traffic safety at road intersections and enable congestion avoidance. However, detailed knowledge about the wireless propagation channel is needed for the development and realistic assessment of V2V communication systems. We present a novel geometry-based stochastic MIMO channel model with support for frequencies in the band of 5.2-6.2 G

Large intelligent surface (LIS) is a new technology yet to be developed. However, this technology is likely to be implemented using cheap components so as to facilitate its deployment. Therefore, we can expect a performance degradation due to hardware impairments. In this paper, we present a model for these hardware impairments in a receiving LIS and we analyze their effect on the achievable rate

We have investigated the charge transfer mechanism in single crystals of DTBDT-TCNQ and DTBDT-F4TCNQ (where DTBDT is dithieno[2,3-d;2′,3′-d′] benzo[1,2-b;4,5-b′]dithiophene) using a combination of near-edge X-ray absorption spectroscopy (NEXAFS) and density functional theory calculations (DFT) including final state effects beyond the sudden state approximation. In particular, we find that a descri

Objective: This study investigated the effect of alpha-ketoglutarate sodium salt (AKG) and ipriflavone (IP) treatment on the mineralization of the tibia in male rats during the development and after the establishment of osteopenia. Design: One hundred and twenty eight male rats were randomly selected and submitted to either sham-operation (SHO) or orchidectomy (ORX), after which each group were th

Comprehensive approaches to predict performance of wood products are requested by international standards, and the first attempts have been made in the frame of European research projects. However, there is still an imminent need for a methodology to implement the durability and moisture performance of wood in an engineering design method and performance classification system. The aim of this stud