Large intelligent surfaces (LIS) are a new trend to achieve higher spectral efficiency and signal-to-noise ratio in mobile communications. For this reason, this paper proposes metrics to analyze the performance of systems with multiple antennas aided by LIS and derive the spectral efficiency, secrecy outage probability, and bit error probability in an environment with Nakagami- distributed fading. In addition to an eavesdropper, there is a single-antenna user, an array of antennas at the transmitter side and the possibility of a direct link between transmitter and receiver. This study assumes that the LIS performs non-ideal phase cancellation leading to a residual phase error that follows a Von Mises distribution, and shows that the resulting channel can be accurately approximated by a Gamma distributed SNR whose parameters are analytically derived. From these formulas, it is possible to evaluate the effect of the strength of the line-of-sight link by varying the Nakagami parameter, .
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8534998 | PMC |
http://dx.doi.org/10.3390/e23101284 | DOI Listing |
Sensors (Basel)
December 2024
School of Mathematics and Statistics, Guangdong University of Technology, Guangzhou 510006, China.
This paper proposes the fixed-time prescribed performance optimal consensus control method for stochastic nonlinear multi-agent systems with sensor faults. The consensus error converges to the prescribed performance bounds in fixed-time by an improved performance function and coordinate transformation. Due to the unknown faults in sensors, the system states cannot be gained correctly; therefore, an adaptive compensation strategy is constructed based on the approximation capabilities of neural networks to solve the negative impact of sensor failures.
View Article and Find Full Text PDFNutrients
December 2024
Institute of Clinical Chemistry and Laboratory Medicine, University Medicine Greifswald, 17475 Greifswald, Germany.
Background: The Geriatric Nutritional Risk Index (GNRI) has shown promising potential for identifying individuals at risk for osteoporosis in various patient cohorts. However, data from the general population confirming or refuting the usefulness of the GNRI as a risk factor for osteoporosis are sparse. We therefore aimed to clarify whether the GNRI is associated with the ultrasound-based bone stiffness index and the osteoporotic fracture risk in a sample of elderly men and women from the general population.
View Article and Find Full Text PDFMicromachines (Basel)
November 2024
School of Computer and Artificial Intelligence, Wuhan University of Technology, Wuhan 430070, China.
With vertical stacking, 3D NAND's flash memory can achieve continuous capacity growth. However, the endurance variation between the stacked layers becomes more and more significant due to process variation, which will lead to the underutilization of many pages and seriously affect the lifetime of 3D NAND's flash memory. We investigated the endurance variation characteristics between layers and divided the stacked layers into the top, middle, and bottom layers according to the endurance characteristics.
View Article and Find Full Text PDFJ Clin Med
December 2024
Sensho-kai Eye Institute, Minamiyama 50-1, Iseda, Kyoto 611-0043, Japan.
The objective of this study was to evaluate the impact of diabetes mellitus (DM) on the outcome of Schlemm's canal-based minimally invasive glaucoma surgery (MIGS). : In a retrospective interventional cohort study, postoperative intraocular pressure (IOP) and intracameral bleeding were analyzed in 25 diabetic patients and 84 non-diabetic patients, with primary open-angle glaucoma (POAG) or ocular hypertension (OH). : The mean follow-up period for all 109 eyes was 35.
View Article and Find Full Text PDFEntropy (Basel)
December 2024
Department of Electrical and Computer Engineering, American University of Beirut, P.O. Box 11-0236, Beirut 1107 2020, Lebanon.
The isotropic Cauchy distribution is a member of the central α-stable family that plays a role in the set of heavy-tailed distributions similar to that of the Gaussian density among finite second-moment laws. Given a sequence of observations, we are interested in characterizing the performance of Likelihood Ratio Tests, where two hypotheses are plausible for the observed quantities: either isotropic Cauchy or isotropic Gaussian. Under various setups, we show that the probability of error of such detectors is not always exponentially decaying with , with the leading term in the exponent shown to be logarithmic instead, and we determine the constants in that leading term.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!