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Over-the-Air Performance Evaluation in Indoor and Outdoor Multipath Propagation Channels of Antenna Diversity Systems inside Anechoic Chamber
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作者 Alaa Choumane Ahmad El Sayed Ahmad +1 位作者 Khaled Khoder Alaa Saleh 《Wireless Engineering and Technology》 2020年第4期31-43,共13页
With the ever-growing requirement for higher data rates, terminals supporting multiple-input multiple-output (MIMO) technologies are being developed for next-generation. As for wireless device manufacturers, a radio p... With the ever-growing requirement for higher data rates, terminals supporting multiple-input multiple-output (MIMO) technologies are being developed for next-generation. As for wireless device manufacturers, a radio performance evaluation of multi-antenna terminals in desired environments is mandatory before product release. This paper discusses the Over the Air (OTA) performance evaluation of antenna diversity systems in Indoor and Outdoor multi-path propagation channel models inside anechoic chamber, in terms of correlation coefficients and diversity gain (DG). These channel models have been emulated in terms of angles of arrivals (AoA) and cross-polarization ratio (XPR) with Rayleigh fading. For this purpose, SATIMO SG24 measurement system has been used. However, the actual configuration of this system is not able to emulate desired realistic environments. Therefore, an innovative methodology based on the SG24 probes control has been developed. The obtained results in simulations and measurements have shown a good agreement. 展开更多
关键词 OTA Testing diversity Measurements INDOOR OUTDOOR MIMO diversity parameters
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Evaluation of seed quality and oil parameters in native Iranian almond(Prunus L.spp.) species
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作者 Soghra Kiani Shakiba Rajabpoor +1 位作者 Karim Sorkheh Sezai Ercisli 《Journal of Forestry Research》 SCIE CAS CSCD 2015年第1期115-122,共8页
We assessed chemical composition and variation in oil content and seed weight of 40 wild-growing almonds(Prunus L. spp.) accessions collected from different parts of Iran. There were significant differences in kerne... We assessed chemical composition and variation in oil content and seed weight of 40 wild-growing almonds(Prunus L. spp.) accessions collected from different parts of Iran. There were significant differences in kernel weight and oil parameters. Accessions ranged from0.20 to 1.5 g in kernel weight, 0.2–3.0 mm in shell thickness, and 16–55 % in oil content. The predominant vegetable oil components of kernels were 4.6–9.5 % palmitic acid, 0.4–0.8 % palmitoleic acid, 1.0–3.4 % stearic acid,48.8–88.4 % oleic acid and 11.3–33.2 % linoleic acid.Linolenic acid was detected in 15 accessions. High heritability was recorded for all studied traits and was maximum for shell thickness(98.5 %) and minimum for oil content(97.1 %). Maximum and minimum ‘Euclidean'pair wise dissimilarities were 17.9 and 0.5, respectively.All 40 accessions were grouped into two major clusters. 展开更多
关键词 Genetic diversity Kernel quality Oil parameters Wild almond(Prunus L.spp.)
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Computer Modelling of Compact 28/38 GHz Dual-Band Antenna for Millimeter-Wave 5G Applications
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作者 Amit V.Patel Arpan Desai +5 位作者 Issa Elfergani Hiren Mewada Chemseddine Zebiri Keyur Mahant Jonathan Rodriguez Raed Abd-Alhameed 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第12期2867-2879,共13页
A four-element compact dual-band patch antenna having a common ground plane operating at 28/38 GHz is proposed formillimeter-wave communication systems in this paper.Themultiple-input-multiple-output(MIMO)antenna geom... A four-element compact dual-band patch antenna having a common ground plane operating at 28/38 GHz is proposed formillimeter-wave communication systems in this paper.Themultiple-input-multiple-output(MIMO)antenna geometry consists of a slotted ellipse enclosed within a hollow circle which is orthogonally rotated with a connected partial ground at the back.The overall size of the four elements MIMO antenna is 2.24λ×2.24λ(at 27.12GHz).The prototype of four-element MIMOresonator is designed and printed using Rogers RTDuroid 5880 withε_(r)=2.2 and loss tangent=0.0009 and having a thickness of 0.8 mm.It covers dual-band having a fractional bandwidth of 15.7%(27.12-31.34 GHz)and 4.2%(37.21-38.81 GHz)for millimeter-wave applications with a gain of more than 4 dBi at both bands.The proposed antenna analysis in terms ofMIMOdiversity parameters(Envelope Correlation Coefficient(ECC)and Diversity Gain(DG))is also carried out.The experimental result in terms of reflection coefficient,radiation pattern,gain and MIMOdiversity parameter correlates very well with the simulated ones that show the potential of the proposed design for MIMO applications at millimeter-wave frequencies. 展开更多
关键词 Connected ground diversity parameters dual-band antenna fifth generation(5G) mmwave multiple input multiple output(MIMO)
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Cattle Conservation in the 21st Century: A Mini Review
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作者 Umar-Faruq Olayinka Bolaji Afees Abiola Ajasa +2 位作者 Ridwan Olawale Ahmed Semiu Folaniyi Bello Obiajulu Emenike Ositanwosu 《Open Journal of Animal Sciences》 2021年第2期304-332,共29页
Cattle are arguably the most important livestock species. Since the beginning of this century, the loss of genetic diversity within this species has been a major concern as this could have serious consequences on the ... Cattle are arguably the most important livestock species. Since the beginning of this century, the loss of genetic diversity within this species has been a major concern as this could have serious consequences on the ability of this species to respond to future production constraints. Genetic diversity has traditionally been accessed from pedigree, however, with the advances in molecular genetics new opportunities have emerged. We examined different methods for accessing genetic diversity and estimating genetic diversity parameters at the genomic level. We also examined criteria and strategies for the conservation of animal genetic resources. Finally, we examined genomic studies on some endangered cattle breeds. 展开更多
关键词 Genetic diversity CONSERVATION Genetic diversity parameters CATTLE
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Geometric interpretation of several classical iterative methods for linear system of equations and diverse relaxation parameter of the SOR method 被引量:2
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作者 LU Xing-jiang LEI Lai-i 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2013年第3期269-278,共10页
Two kinds of iterative methods are designed to solve the linear system of equations, we obtain a new interpretation in terms of a geometric concept. Therefore, we have a better insight into the essence of the iterativ... Two kinds of iterative methods are designed to solve the linear system of equations, we obtain a new interpretation in terms of a geometric concept. Therefore, we have a better insight into the essence of the iterative methods and provide a reference for further study and design. Finally, a new iterative method is designed named as the diverse relaxation parameter of the SOR method which, in particular, demonstrates the geometric characteristics. Many examples prove that the method is quite effective. 展开更多
关键词 linear equation iterative method geometric explanation diverse relaxation parameter SORmethod.
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Compact spectral-polarization-modulation method for rapid and versatile polarization measurements in interferometric imaging
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作者 DI YANG WEIKE WANG +2 位作者 SONGWEN XU ZHUOQUN YUAN YANMEI LIANG 《Photonics Research》 2025年第4期1049-1059,共11页
Polarization-based detection technologies have broad applications across various fields.Integrating polarization with interferometric imaging holds significant promise for simultaneously capturing three-dimensional st... Polarization-based detection technologies have broad applications across various fields.Integrating polarization with interferometric imaging holds significant promise for simultaneously capturing three-dimensional structure and polarization information.However,existing interferometric polarization measurement methods often rely on complex setups and sacrifice the acquisition rate or axial imaging range for parameter diversity. 展开更多
关键词 three dimensional structure compact spectral polarization modulation rapid polarization measurements polarization based detection interferometric imaging parameter diversity interferometric polarization measurement complex setups
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