3,304 research outputs found
Electromagnetic Lens-focusing Antenna Enabled Massive MIMO: Performance Improvement and Cost Reduction
Massive multiple-input multiple-output (MIMO) techniques have been recently
advanced to tremendously improve the performance of wireless communication
networks. However, the use of very large antenna arrays at the base stations
(BSs) brings new issues, such as the significantly increased hardware and
signal processing costs. In order to reap the enormous gain of massive MIMO and
yet reduce its cost to an affordable level, this paper proposes a novel system
design by integrating an electromagnetic (EM) lens with the large antenna
array, termed the EM-lens enabled MIMO. The EM lens has the capability of
focusing the power of an incident wave to a small area of the antenna array,
while the location of the focal area varies with the angle of arrival (AoA) of
the wave. Therefore, in practical scenarios where the arriving signals from
geographically separated users have different AoAs, the EM-lens enabled system
provides two new benefits, namely energy focusing and spatial interference
rejection. By taking into account the effects of imperfect channel estimation
via pilot-assisted training, in this paper we analytically show that the
average received signal-to-noise ratio (SNR) in both the single-user and
multiuser uplink transmissions can be strictly improved by the EM-lens enabled
system. Furthermore, we demonstrate that the proposed design makes it possible
to considerably reduce the hardware and signal processing costs with only
slight degradations in performance. To this end, two complexity/cost reduction
schemes are proposed, which are small-MIMO processing with parallel receiver
filtering applied over subgroups of antennas to reduce the computational
complexity, and channel covariance based antenna selection to reduce the
required number of radio frequency (RF) chains. Numerical results are provided
to corroborate our analysis.Comment: 30 pages, 9 figure
On the Relation of Exercising of Patent Rights and Antimonopoly Law
Antimonopoly law provides exemption for the legitimate exercising of patent rights, casts regulation and control over the patent abuse. This article expounds the exemption subject, exemption condition, exemption occasion as well as exemption category, elucidates the relation of abuse behavior and antimonopoly law, puts forward concrete regulating approach on the patent abuse by antimonopoly law. Key words: legitimate exercising of patent rights, patent abuse, antimonopoly law RĂ©sumĂ©: le juste exercice du droit de propriĂ©tĂ© industrielle est immunisĂ© selon la loi antitrust, jâexpose dans cette thĂšse lâobjet, la condition, lâoccasion et la catĂ©gorie de son immunitĂ©. Pourtant, lâabus du droit de propriĂ©tĂ© industrielle est restreint aussi selon la loi antitrust, jâexplique la relation entre lâabus du droit de propriĂ©tĂ© industrielle et la loi antitrust, puis propose mon projet afin de restreindre lâabus du droit de propriĂ©tĂ© industrielle par la loi antitrust. Mots-ClĂ©s: le juste exercice du droit de propriĂ©tĂ© industrielle, lâabus du droit de propriĂ©tĂ© industrielle, la loi antitrus
Law-economics Analysis for the Restriction of Intellectual
The restriction of Intellectual property rights, as an important principle and system in the Intellectual property law, has its own existence of the reasonable economic basis. This thesis begins with the definition of intellectual asset rights, reveals that the intellectual asset has the double properties of private products and public products, and demonstrates the rationality of moderate private right protection. And then it revises the economic senses in the intellectual property system using the method of economic analysis, and analyzes the important role which intrinsic balance mechanism and exterior restriction mechanism play, to guarantee information resource configured liquidly and carried on effectively. Key words: Law-economics, Restriction of intellectual property rights, Pareto criterion RĂ©sumĂ©: En tant que le principe et lâinstitution importants du droit de propriĂ©tĂ© intellectuelle, la restriction du droit de propriĂ©tĂ© intellectuelle existe sur la base rationnelle de la science Ă©conomique. Je commence dans cette thĂšse par la dĂ©limitation du droit de propriĂ©tĂ© intellectuelle afin de dĂ©couvrir sa double caractĂ©ristique: produit privĂ© et produit public, et dâargumenter la rationalitĂ© de le protĂ©ger mesurĂ©ment comme le droit privĂ©. Et ensuite, jâĂ©tudie la raison Ă©conomique de lâinstitution du droit de propriĂ©tĂ© intellectuelle, au moyen dâanalyse Ă©conomique, et jâexplique lâimportance de son mĂ©canisme Ă©quilibrĂ© Ă lâintĂ©rieur et son mĂ©canisme restreint Ă lâextĂ©rieur pour assurer la distribution facile et la fonction effective des resources informatiques. Mots-ClĂ©s: droit-Ă©conomie, restriction du droit de propriĂ©tĂ© intellectuelle, critĂšre de PARET
NâČ-DiphenylÂmethylÂene-2-hydroxyÂbenzohydrazide
The title compound, C20H16N2O2, was synthesized by the reaction of 2-hydroxyÂbenzohydrazide with diphenylÂmethanone. The dihedral angle between the phenyl rings is 76.28â
(11)°. The amino H atom is involved in an intraÂmolecular NâHâŻO hydrogen bond. In the crystal structure, the hydrÂoxy groups and carbonyl O atoms form interÂmolecular OâHâŻO hydrogen bonds, which link the molÂecules into chains running along the b axis
Revisit assignments of the new excited states with QCD sum rules
In this article, we distinguish the contributions of the positive parity and
negative parity states, study the masses and pole residues of the
1S, 1P, 2S and 2P states with the spin and
using the QCD sum rules in a consistent way, and revisit the
assignments of the new narrow excited states. The predictions
support assigning the to be the 1P state with
, assigning the to be the 1P
state with or the 2S state with
, and assigning to be the 2S
state with .Comment: 19 pages, 22 figures. arXiv admin note: text overlap with
arXiv:1705.0774
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