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.
The body concept in the human sciences received significant attention through study and investigation, and has been dealt with by many studies, yet this research is an attempt to reveal the body transformations and its concept in the visualized picture (drawing field) in general and in the drawings of the artist Muhammed Mehraddin in specific. Therefore, the approach of the body, philosophically and technically, in this field has its nature and specificity in revealing the structures and relations in employing the body as a visual, spatially and temporally indicator through the drawing fields of the artist Muhammed Mehraddin, assuming that the body, for the artist's works, constitutes a cultural, artistic performance focus in his a
... Show MoreThe research deals with an important detail of the joints of the film industry and television drama, which is the expression and aesthetic of the long shot, after being popularized by some directors, and that the long shot has been employed since the beginning of the cinema. But the research addresses the contemporary film and how the long shot worked. The researcher identified her goal in identifying the aesthetic and expressive of the long shot in the contemporary film, and then defined the term of the shot and the long shot.
The theoretical framework was based on two topics: the first (aesthetic and artistic expression in cinema) and the second (the long shot and the state of its construction). The researcher then chose LA LA LAND
This paper uses classical and shrinkage estimators to estimate the system reliability (R) in the stress-strength model when the stress and strength follow the Inverse Chen distribution (ICD). The comparisons of the proposed estimators have been presented using a simulation that depends on the mean squared error (MSE) criteria.
The increased food requirement puts intense pressure on the agriculture community to grow more from the same resources resulting in people leaving the farming business. This happened not exclusively due to the industrial pressure to produce more but to the lack of technology adoption among growers. The use of the sensor in agriculture is not new, but its adoption among agriculture producers is a challenge for industry and scientists. This study aimed to determine sensors used in agricultural fields with challenges and prospects. The study found that sensors have successfully been used at the industry level with highly skilled labor; however, their adoption is challenging in rural agriculture systems due to the lack of a support
... Show MoreIn this study abundance and composition of zooplanktons in the Indus River Estuary was conducted to examine habitat characteristics and its impact on tiny organisms. Overall 30,656 individuals were identified and segregated into seven major groups including Copepods, Cnidarians, Decapods, Mollusk, Pisces, Amphipods and Chaetognaths. For better understanding they were further divided into eighteen planktonic categories. Among them Lucifer spp. comprises of 52.21% was the most abundant group with a peak appeared in March whereas Chaetognaths were rarely observed in the entire study period. Species diversity exhibited a mixed trend with the highest values (0.776) of dominance observed in spring (March). The results of Canonical Corresponden
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The Iraqi government seeks to overcome the financial crisis by investing and privatizing some projects to achieve sustainable growth. Most of the investment projects in Iraq suffer from many constraints that greatly impact the success of these projects. A survey of the opinions of a group of experts was conducted to identify the most important constraints facing the investment process in Iraq. Then the experts' answers were arranged in a closed questionnaire and distributed to the research sample for which the statistical analysis was conducted. Through it, the most important (17) factors that had the greatest impact on the failure of investment projects in Iraq were reached. One of the main constraints was
... Show MoreRainwater harvesting is one of the available solutions to overcome water scarcity in arid and semi-arid regions with highly variable rainfall and unexpected periods of drought or floods. This study aims to identify the best rainwater harvesting system in Al-Muthanna governorate using Remote Sensing (RS) and Geographic Information System (GIS) techniques. Landsat 8 images were used to produce the land use map which shows five different classes: water (0.2%), bare soil (82.11%), built-up (15.71%), forest (0.27%), and farmland and grass (1.71%). The results revealed that the rainwater harvesting system can be applied only in the north and north-eastern parts of the study area which consists of residential and agricultural areas and
... Show MoreThe composition of fish assemblages in Iraqi marine water was assessed. 91 species belonging to 71 genes and 47 families of Osteichthyes and 13 species of Conderchthyes were collected during the study period from January to December 2018, using trawl net fishing. Three stations were selected, where two new species (Siganus javus and Gobiopsis sp.) and reclassification of Torpedo panthera where identified and two species of freshwater fish (Oreochromis niloticus and Oreochromis aureus) were first recorded in marine waters. The highest numbers of species were 32 and 42 for the first and second stations, respectively, recorded in October , while 55 species were recorded in the third s
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