List of Articles رادیو شناختگر

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  1 - Bi-Threshold Cooperative Spectrum Sensing With the Ability of Simultaneous Improving Throughput and Reducing Energy Consumption in Cognitive Radio Network
  Masoud Moradkhani Farzad Soltanian
  10.30495/jce.2023.1989614.1211
  By performing cooperative spectrum sensing in a cognitive radio network, although the network throughput increases with the increase in the number of secondary users, but at the same time, it also causes an increase in energy consumption. This makes it necessary to prov More

  By performing cooperative spectrum sensing in a cognitive radio network, although the network throughput increases with the increase in the number of secondary users, but at the same time, it also causes an increase in energy consumption. This makes it necessary to provide a system that is able to create a tradeoff between throughput and energy consumption. In contrast to the conventional method of spectrum sensing based on one detection threshold, spectrum sensing with double thresholds avoids reporting unreliable data to the fusion center, thus potentially leading to greater energy saving. In this paper, a double threshold spectrum sensing cognitive radio network with a non-ideal reporting channel is optimized. The values of the threshold and the sensing time are jointly optimized to maximize the throughput of the network, provided that the network energy consumption and the amount of interference with the primary users are limited. The optimization problem is formulated and a numerical method is presented to solve it. The simulation results show a flexible system that can simultaneously provide higher throughput and lower energy consumption than the conventional sensing method. These results, while confirming the higher tolerance against the error of the reporting channel, show a significant energy saving of up to 70% by guaranteeing the throughput efficiency greater than 1. Manuscript profile
• Open Access Article
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  2 - Resource Allocation Parameters Improvement in Interference-Based Cognitive Radio
  Sayyed Majid Mazinani Ali Hasan Nezhad
  Interference Alignment is an efficient method of reducing interference in wireless networks, which can be used in radio cognitive networks. In the interference alignment, a suitable pre-encoder matrix will be found in each transmitter that all interferences are limited More

  Interference Alignment is an efficient method of reducing interference in wireless networks, which can be used in radio cognitive networks. In the interference alignment, a suitable pre-encoder matrix will be found in each transmitter that all interferences are limited to a part of the signal subspace in each receiver, which causes the desired signal to be placed in the other part. Therefore, the desired signal can be easily received by a suitable interference removal filter. In this paper, an efficient method for using interference homogeneity in a cognitive radio network is presented. In the proposed method, the selection of radiation vectors for the formation of selection vectors based on adjacent vectors is done in equal steps. Selecting equal steps improves the convergence speed of the algorithm. The results show that computational efficiency and complexity have been greatly improved. To evaluate the proposed method of power allocation in the network, they are evaluated to maximize the network energy efficiency and the other to maximize the total rate of the cognitive radio network while keeping the initial user rate at the threshold level. The simulation results reveal the improvement of network performance using this method in both strategies. Manuscript profile