902 research outputs found
Network meta-analysis of migraine disorder treatment by NSAIDs and triptans
Node splitting of direct and indirect comparisons according to type of interventions for rescue medication and recurrence. (EPS 1963 kb
A recurrent plot based stochastic nonlinear ray propagation model for underwater signal propagation
A stochastic nonlinear ray propagation model is proposed to carry out an exploration of the nonlinear ray theory in underwater signal propagation. The recurrence plot method is proposed to quantify the ray chaos and stochastics to optimize the model. Based on this method, the distribution function of the control parameter δ is derived. Experiments and simulations indicate that this stochastic nonlinear ray propagation model provides a good explanation and description on the stochastic frequency shift in underwater signal propagation.Major State Basic Research Development Program of China https://doi.org/10.13039/501100012336RF Goverment GrantNational Nature Science Fundation of ChinaPeer Reviewe
Hybrid RIS-Assisted MIMO Dual-Function Radar-Communication System
Dual-function radar-communication (DFRC) technology is emerging in
next-generation wireless systems. Reconfigurable intelligent surface (RIS)
arrays have been suggested as a crucial sensor component of the DFRC. In this
paper, we propose a hybrid RIS (HRIS)-assisted multiple-input multiple-output
(MIMO) DFRC system, where the HRIS is capable of reflecting communication
signals to mobile users and receiving the scattering signal reflected from the
radar target simultaneously. Under such a scenario, we are interested in
characterizing the fundamental trade-off between radar sensing and
communication. Specifically, we study the joint design of the beamforming
vectors at the base station (BS) and the parameter configuration of the HRIS so
as to maximize the signal-to-interference-and-noise ratio (SINR) of the radar
while guaranteeing a communication SINR requirement. To solve the formulated
non-convex beamforming design problem, we propose an efficient alternating
optimization approach. In particular, for fixed beams at the BS, we use a fast
grid search-assisted auto gradient descent (FGS-AGD) algorithm to seek the best
HRIS configuration; Then, a closed-form BS beamforming solution is obtained
using semidefinite relaxation. Numerical results indicate that compared with
benchmark schemes, the proposed approach is capable of improving the radar
performance and communication quality significantly and simultaneously
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