List of Articles NOMA

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  1 - Complexity Reduction in Massive-MIMO-NOMA SIC Receiver in Presence of Imperfect CSI
  Nilufar Tutunchi Afrooz Haghbin Behrad Mahboobi
  10.29252/jist.8.30.113
  One of the main reasons for switching to the next generation of communication systems is the demand of increasing capacity and network connections. This goal can be achieved using massive multiple input - multiple output (massive-MIMO) systems in combination with Non-or More

  One of the main reasons for switching to the next generation of communication systems is the demand of increasing capacity and network connections. This goal can be achieved using massive multiple input - multiple output (massive-MIMO) systems in combination with Non-orthogonal multiple access (NOMA) technique. NOMA technology uses the successive interference cancellation (SIC) receiver to detect user’s signals which imposes an additional complexity on the system. In this paper, we proposed two methods to reduce the system complexity. The proposed method despite imperfect channel state information (CSI) in the receiver, there is not significantly reduction in the system performance. Since the computation of matrices inverse has a high computational complexity, we used the Neumann series approximation method and the Gauss-Seidel decomposition method to compute matrices inverse in the SIC receiver. Simulation results are provided at the end of the paper in terms of bit error rate (BER) at the receiver which show, these methods have lower computational complexity in comparison with the traditional methods while they cause a slight performance reduction in the SIC receiver. Also, we examined the increasing and decreasing value of imperfect channel state information in the system performance which shows the increasing value of imperfect channel state information, cause a slight performance reduction in SIC receiver. Manuscript profile
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  2 - Energy-Efficient User Pairing and Power Allocation for Granted Uplink-NOMA in UAV Communication Systems
  Seyed Hadi Mostafavi-Amjad Vahid Solouk Hashem Kalbkhani
  10.52547/jist.27369.10.40.312
  With the rapid deployment of users and increasing demands for mobile data, communication networks with high capacity are needed more than ever. Furthermore, there are several challenges, such as providing efficient coverage and reducing power consumption. To tackle thes More

  With the rapid deployment of users and increasing demands for mobile data, communication networks with high capacity are needed more than ever. Furthermore, there are several challenges, such as providing efficient coverage and reducing power consumption. To tackle these challenges, using unmanned aerial vehicles (UAVs) would be a good choice. This paper proposes a scheme for uplink non-orthogonal multiple access (NOMA) in UAV communication systems in the presence of granted and grant-free users. At first, the service area users, including granted and grant-free users, are partitioned into some clusters. We propose that the hover location for each cluster is determined considering the weighted mean of users’ locations. We aim to allocate transmission power and form NOMA pairs to maximize the energy efficiency in each cluster subject to the constraints on spectral efficiency and total transmission power. To this end, the transmission powers of each possible pair are obtained, and then Hungarian matching is used to select the best pairs. Finally, finding the flight path of the UAV is modeled by the traveling salesman problem (TSP), and the genetic algorithm method obtains its solution. The results show that the increasing height of the UAV and density of users increases the spectral and energy efficiencies and reduces the outage probability. Also, considering the quality of service (QoS) of granted users for determining the UAV's hover location enhances the transmission's performance. Manuscript profile
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  3 - Comparative study of nomadic quality of life indicators in the pre- and post accommodation periods caused by floods Case study: Azadegan village, Anbarabad County
  mohammad amin khorasani
  Having a good quality of life has always been a human desire. Quality of life in rural areas depends on many factors such as employment, adequate income, access to services such as education and health, health, social security so that factors such as low density of rura More

  Having a good quality of life has always been a human desire. Quality of life in rural areas depends on many factors such as employment, adequate income, access to services such as education and health, health, social security so that factors such as low density of rural settlements, reduced employment and income in the agricultural sector, Inadequate and inefficient communication routes and transportation networks have complicated the implementation of policies necessary to improve the quality of rural life. With this view, the purpose of this study is to study and compare the quality of life indicators before settlement and presence in the nomadic environment and after settlement in Azadegan village after the flood. The research method in this research is descriptive-analytical, based on library-field studies (questionnaire) and searching Internet sites. In order to analyze the data, SPSS software t-test was used. The findings show that the quality of life indicators before and after settlement in Azadegan village with a significant level of less than 0.05% had no positive effects in Azadegan village. Also, the results showed that the components of employment and income in Azadegan village located in Jiroft city did not have a positive effect on job creation for the villagers. Manuscript profile