Preferred Language
Articles
/
6hYJBYcBVTCNdQwCYS2X
Downlink Training Design for FDD Massive MIMO Systems in the Presence of Colored Noise
...Show More Authors

Massive multiple-input multiple-output (MaMi) systems have attracted much research attention during the last few years. This is because MaMi systems are able to achieve a remarkable improvement in data rate and thus meet the immensely ongoing traffic demands required by the future wireless networks. To date, the downlink training sequence (DTS) for the frequency division duplex (FDD) MaMi communications systems have been designed based on the idealistic assumption of white noise environments. However, it is essential and more practical to consider the colored noise environments when designing an efficient DTS for channel estimation. To this end, this paper proposes a new DTS design by exploring the joint use of spatial channel and noise covariance matrices, when the channel is not reciprocal but the coherence block length remains limited. We derive an analytical solution for the mean square error (MSE) based on the proposed training design with colored noise. In addition, this paper exploits the method of random matrix theory to provide an analytical solution for the downlink (DL) achievable sum rate of the regularized zero forcing beamforming (RZFBF) precoder. Numerical results demonstrate that using the proposed DTS design, the MSE of the channel estimate is significantly reduced compared with the conventional training designs with white noise. Furthermore, the results show that the proposed pilot design markedly improves the DL achievable SR over the conventional training designs, especially at relatively low signal-to-noise-ratio (SNR) levels. This enables FDD MaMi systems to operate under more practical scenarios of colored noise and limited coherence time environments.

Scopus Clarivate Crossref
View Publication
Publication Date
Mon Oct 01 2018
Journal Name
Radioelectronics And Communications Systems
Optical CDMA Coded STBC Based on Chaotic Technique in FSO Communication Systems
...Show More Authors

Free-Space Optical (FSO) can provide high-speed communications when the effect of turbulence is not serious. However, Space-Time-Block-Code (STBC) is a good candidate to mitigate this seriousness. This paper proposes a hybrid of an Optical Code Division Multiple Access (OCDMA) and STBC in FSO communication for last mile solutions, where access to remote areas is complicated. The main weakness effecting a FSO link is the atmospheric turbulence. The feasibility of employing STBC in OCDMA is to mitigate these effects. The current work evaluates the Bit-Error-Rate (BER) performance of OCDMA operating under the scintillation effect, where this effect can be described by the gamma-gamma model. The most obvious finding to emerge from the analysis

... Show More
View Publication
Scopus (5)
Crossref (4)
Scopus Crossref
Publication Date
Sun Jun 12 2022
Journal Name
Sensors
Recent Advances in Bipedal Walking Robots: Review of Gait, Drive, Sensors and Control Systems
...Show More Authors

Currently, there is an intensive development of bipedal walking robots. The most known solutions are based on the use of the principles of human gait created in nature during evolution. Modernbipedal robots are also based on the locomotion manners of birds. This review presents the current state of the art of bipedal walking robots based on natural bipedal movements (human and bird) as well as on innovative synthetic solutions. Firstly, an overview of the scientific analysis of human gait is provided as a basis for the design of bipedal robots. The full human gait cycle that consists of two main phases is analysed and the attention is paid to the problem of balance and stability, especially in the single support phase when the biped

... Show More
View Publication Preview PDF
Scopus (61)
Crossref (44)
Scopus Clarivate Crossref
Publication Date
Fri Jan 05 2024
Journal Name
Al-academy
Problematic theatrical landscape design Between the director and designer
...Show More Authors

This research discussed analytically based on intellectual institutions and theoretical landscape theater as artistic phenomenon depends on the compounds interacting overlapping mechanism visualization and dazzling Whatever the dilemma it a set of Alaqcar differ among themselves but in the result unit intellectual holds through difference and diversity between trends and styles and ways in design theorist theatrics Valashkalah on apparently formed through variations and different points of view through the philosophy of transformation and interpretation and assignment to offer privacy.
Valashkalah pulled in the design theorist theatrical as system training to arrange time and place and in line with the interpretation of speech text an

... Show More
View Publication Preview PDF
Publication Date
Wed May 02 2012
Journal Name
Journal Of Planner And Development
the planning and design characteristics of Iraqs mud building and settlement
...Show More Authors

The Mesopotamian soil is muddy and fertile, and so from ancient eras Iraqis used mud in their building, settlements and architecture in different methodologies according to the nature and the function of the building that was either in its pure form or by mixing it with other materials such as straw . also as raw bricks in different ways either for the whale building or parts of it, or for the finishing parts such as roofing for instance. In this research these different forms and methodologies will permeate through out a chosen examples of historical building, rural buildings and settlements and ancient buildings as well as some current uses of mud in the structures and building in standing cities, this in order to conclude some

... Show More
View Publication
Publication Date
Fri Jan 01 2021
Journal Name
International Journal Of Agriculture And Statistical Science
COMPARISON OF FORECASTING OF THE RISK OF CORONAVIRUS (COVID-19) IN HIGH-QUALITY AND LOW-QUALITY HEALTHCARE SYSTEMS, USING ANN MODELS
...Show More Authors

COVID-19 is a disease that has abnormal over 170 nations worldwide. The number of infected people (either sick or dead) has been growing at a worrying ratio in virtually all the affected countries. Forecasting procedures can be instructed so helping in scheming well plans and in captivating creative conclusions. These procedures measure the conditions of the previous thus allowing well forecasts around the state to arise in the future. These predictions strength helps to make contradiction of likely pressures and significances. Forecasting procedures production a very main character in elastic precise predictions. In this case study used two models in order to diagnose optimal approach by compared the outputs. This study was introduce

... Show More
Preview PDF
Scopus (3)
Scopus
Publication Date
Wed Feb 15 2023
Journal Name
International Journal Of Emerging Technologies In Learning (ijet)
Instructional Design According to the Repulsive Learning Model and its Impact on the Achievement of Chemistry and Lateral Thinking for Third-Grade Intermediate Students
...Show More Authors

Identify the effect of an educational design according to the repulsive (allosteric) learning model on the achievement of chemistry and lateral thinking. The sample consisted of (59) students from third-grade intermediate students. They were randomly distributed into two groups (experimental and control), and the equivalence was done in (chronological age, previous achievement in chemistry, intelligence, lateral thinking). The (30) students from experimental group were taught according to the instructional design, other 29 students from the (control) group were taught according to the usual method. Two tests done, one of them is an achievement test consisted of (30) items of the type of multiple choice, the other was a lateral think

... Show More
View Publication
Scopus (1)
Scopus Crossref
Publication Date
Thu Mar 29 2018
Journal Name
Construction Research Congress 2018
Consideration of Worker Safety in the Design Process: A Statistical-Based Approach Using Analysis of Variance (ANOVA)
...Show More Authors

View Publication
Scopus (1)
Crossref (2)
Scopus Crossref
Publication Date
Sun Jan 12 2025
Journal Name
Nasaq
The effectiveness of educational-learning design according to the model of brain compatibility in collection among middle first- grade students in Mathematics
...Show More Authors

The research aimed to identify "the effectiveness of educational-learning design according to the model of brain compatibility in achievement among firstmiddle grade students in mathematics", in schools affiliated with the Second Karkh Directorate of Education. To achieve the goal of research, the following zero hypothesis has been formulated: " There is no statistically significant difference at the semantic level (05.0) between the average scores of experimental group students who will study with design accreditation (educational - learning) according to the brain compatibility model and the grades of control group students who will study in the usual way in the achievement thinking test". The research community, which is represented by

... Show More
View Publication
Publication Date
Wed Mar 01 2023
Journal Name
Iraqi Journal Of Physics
Design and Construction of a Dust Detection System using Infrared Laser: The Case of Dust Storms in Baghdad in the Summer 2022
...Show More Authors

Iraq suffers from serious pollution with harmful particles that have important direct and indirect effects on human activities and human health. In this research, a system for detecting pollutants in the air was designed and manufactured using infrared laser technology. This system was used to detect the presence of pollutants in the dust storms that swept the city of Baghdad which could have a negative impact on human health and living organisms.

The designed detection system based on the use of infrared laser (IR) with a wavelength of 1064 nm was used for the purposes of detecting pollutants based on the scattering of the laser beam from these pollutants. The system was aligned to obtain the best signal for the scattered rays, w

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Jul 02 2017
Journal Name
Journal Of Educational And Psychological Researches
The effectiveness of instructional design according to whole brain theory of Herman in the achievement of chemistry of the fifth scientific students
...Show More Authors

The research aimed to identify the effectiveness of instructional design according to whole brain theory of Herman in the achievement of chemistry at the fifth scientific students at a secondary school of the General Directorate for Educational in Diyala / Baladruz in Iraq. The research sample Consisted of (57 student, (29) students as experimental group studied according to instructional design strategies for whole brain theory of Herrmann and (28) a student as a control group studied by the usual way for two semesters, a prepared achievement test as article and objective type of multiple choice, the coefficient stability of alpha-Cronbach equation reached (0.86). The research Results showed the presence of a statistically significant d

... Show More
View Publication Preview PDF