Multi-beam relays can be used to overcome the non-line-of-sight (NLOS) issues in millimeter-wave (mm-wave) communication networks that serve many users an obstruction-rich environment. We demonstrate a modular multi-beam relay array at 28 GHz, which is scalable and fully decentralized. The individual branches of are independent do not need share timing reference or physically located on same su...

A novel method to generate and manipulate vector vortex beams in an integrated, ring resonator based geometry is proposed. We show numerically that a ring resonator, with an appropriate grating, addressed by a vertically displaced access waveguide emits a complex optical field. The emitted beam possesses a specific polarization topology, and consequently a transverse intensity profile and orbit...

In this paper, iterative multi-user detection techniques for multi-beam communications are presented. The solutions are based on a successive interference cancellation architecture and a channel decoding to treat the co-channel interference. Beams forming and channels coefficients are estimated and updated iteratively. A developed technique of signals combining allows power improvement of the u...

This paper studies interfacial mechanical behavior of laminate beams, consisting of two piezoelectric facial sheets and an elastic core. The study is based on coupled multi-filed finite element formulation. The emphasis is placed on mechanical and electric behavior of interfaces between piezoelectric material and elastic material, including effect of geometrical parameters, stress distribution ...

In computed tomography (CT), the nonlinear attenuation characteristics of polychromatic X-rays cause beam hardening artifacts in the reconstructed images. State-of-theart methods to correct the beam hardening effect are mostly single material precorrections (e.g. water-precorrection), which are far less efficient when more than one material is present in the field of measurement. The use of tho...

The paper introduces a high gain end-fire printed antenna operating at 14 GHz with a bandwidth of 2 GHz. The 3x3 antenna sub-array formed of this element is used to present its beam steering and multi-beam-switching capabilities for millimeter wave Massive MIMO antenna arrays of 5G networks. The co-existence of these two techniques in a Massive MIMO sub-array, aided by the use of a simple two v...

Keeping pace with technological progress, robot sensors are generating increasing amounts of data; a particular recent trend has been a shift from single-beam LIDAR sensors to multi-beam versions. Whereas single-beam sensors can often be calibrated without great difficulty, deriving an accurate calibration for lasers with many simultaneous beams has been a tedious and significantly harder chall...

Beam search is a tree search procedure where, at each level of the tree, at most w nodes are kept. This results in a metaheuristic whose solving time is polynomial in w. Popular for single-objective problems, beam search has only received little attention in the context of multi-objective optimization. By introducing the concepts of oracle and filter, we define a paradigm to understand multi-ob...

A 14.5 GHz ECRIS has been designed and fabricated at KAERI (Korea Atomic Energy Research Institute) to produce multi-charged ion beam (especially for C ion beam) for medical application. The magnet system has cupper conductor solenoid coils and a permanent magnet hexapole. A welded tube with aluminium and stainless steel is used for an ECR plasma chamber to improve the production of secondary e...