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Non-Orthogonal Multiple Access (NOMA) is studied under statistical Channel State Information (CSI) and probabilistic constraints. Unlike the conventional power domain only NOMA, the definition of NOMA here considers both the power and the frequency domains simultaneously, where a flat power spectrum is assumed for each UE. This increases the capacity region when compared to the conventional definiti

For a pair of closely located and cooperating user equipments (UEs), a precoder is designed at the base station (BS) which considers the UE cooperation. The UEs collaborate over an out-of-band side-link with a finite capacity. The side-link may be used for interference cancellation (IC) or for relaying decoded symbols. The precoder has two parts, a cooperative part based on channel inversion and a

We use Markov state models (MSMs) to analyze the dynamics of a β-hairpin-forming peptide in Monte Carlo (MC) simulations with interacting protein crowders, for two different types of crowder proteins [bovine pancreatic trypsin inhibitor (BPTI) and GB1]. In these systems, at the temperature used, the peptide can be folded or unfolded and bound or unbound to crowder molecules. Four or five major fre

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

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

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

In this paper, we perform a threshold analysis of braided convolutional codes on the additive white Gaussian noise (AWGN) channel. The decoding thresholds are estimated by Monte-Carlo density evolution techniques and compared with approximate thresholds from an erasure channel prediction. The results show that, with spatial coupling, the predicted thresholds are very accurate and quickly approach

In multiuser multiple–input multiple–output (MU–MIMO) systems, channel correlation is detrimental to system performance. We demonstrate that widely used, yet overly simplified, correlation models that generate identical correlation profiles for each terminal tend to severely underestimate the system performance. In sharp contrast, more physically motivated models that capture variations in the pow

The Theory of Characteristic Modes (TCM) has recently been shown to be beneficial in solving a wide variety of complex electromagnetic problems. However, there are still open issues in using TCM to analyze objects which consist of simple or complex media. Either a volume integral equation (VIE) or a surface integral equation (SIE) is required to solve for the characteristic modes of these objects.

The 15 and 28 GHz frequency bands have been identified as interesting candidates for future 5G cellular communication systems. In this paper, based on ray-tracing simulations, we investigate the channel capacities at 15 and 28 GHz for a number of different array processing techniques, including beamforming, spatial multiplexing, and two types of hybrid beamforming. This is done for an 8x32 multipl

With increasing number of wirelessly connected devices having limited energy resources, energy efficient solutions become more and more important. Many studies have addressed schemes where low-power wake-up receivers are used to improve energy efficiency in networks with low traffic intensity (per node) and demands on availability. One such scheme is the duty-cycled wake-up receiver medium access

In this paper, full-and sub-structure characteristic modes (CMs) are explored through the effect of coupling between the target and background structures. The eigenvalues and eigen-current distributions of the first few modes are compared for different coupling levels in the numerical example. Similarities and differences between the two types of CMs in specific conditions are revealed, paving the

This paper presents a broadside antenna with three ports operating at the same frequency. The TM030 and TM003 modes of a patch are excited by two coaxial cables to generate two orthogonal linear polarizations. The patch can be transformed into a slotted SIW cavity whose TE201 and TE102 modes are jointly excited by the third cable. A matching cavity and a matching patch are introduced to broaden th

The performance of baseband beamforming in multi-user multiple-input multiple-output (MU-MIMO) systems has been extensively studied for simplified statistical channel models where no angular parameters are taken into account. In contrast, there is little performance analysis with ray-based models, which are more physically motivated, feature prominently in standardization and have been experimenta

BACKGROUND: The cultivated peanut (Arachis hypogaea) is one of the most important oilseed crops worldwide, however, its improvement is restricted by its narrow genetic base. The highly variable wild peanut species, especially within Sect. Arachis, may serve as a rich genetic source of favorable alleles to peanut improvement; Sect. Arachis is the biggest taxonomic section within genus Arachis and i

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

The use of ultra-low power wake-up receivers (WuRx) can significantly reduce idle listening energy cost. To tailor a WuRx scheme to orthogonal frequency division multiplexing (OFDM) based systems, such as LTE-MTC or IEEE 802.11, the wake-up signal (WUS) also needs to follow OFDM principles to avoid interfering with other transmissions in the same shared bandwidth. Here, we address this particular

In this letter, we analyze cluster characteristics in mm wave channel characteristics, based on an indoor channel measurement campaign at 28 GHz. The spatial characteristics of clusters are analyzed, and we investigate the CDFs of the intra cluster angular spreads and the number of clusters. Also we introduce the Random Cluster Number (RCN) feature to the primary module of IMT-2020 channel model,

In this paper, we introduce a novel hybrid multiuser multiple-input multiple-output (MU-MIMO) architecture, with an emphasis on aggressive millimeter-wave (mmWave) hardware reduction methods, omitting the beam selection stage. We propose a simplification in a 28 GHz Rotman lens, where the number of beam-ports are reduced relative to the array ports resulting in the removal of a bank of RF switches