List of articles (by subject) Satellite Communication
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Open Access Article
1 - Enhancing Efficiency of Software Fault Tolerance Techniques in Satellite Motion System
Hoda Banki babamir babamir Azam Farokh Mohammad Mehdi MorovatiThis research shows the influence of using multi-core architecture to reduce the execution time and thus increase performance of some software fault tolerance techniques. According to superiority of N-version Programming and Consensus Recovery Block techniques in compar MoreThis research shows the influence of using multi-core architecture to reduce the execution time and thus increase performance of some software fault tolerance techniques. According to superiority of N-version Programming and Consensus Recovery Block techniques in comparison with other software fault tolerance techniques, implementations were performed based on these two methods. Finally, the comparison between the two methods listed above showed that the Consensus Recovery Block is more reliable. Therefore, in order to improve the performance of this technique, we propose a technique named Improved Consensus Recovery Block technique. In this research, satellite motion system which known as a scientific computing system is consider as a base for our experiments. Because of existing any error in calculation of system may result in defeat in system totally, it shouldn’t contains any error. Also the execution time of system must be acceptable. In our proposed technique, not only performance is higher than the performance of consensus recovery block technique, but also the reliability of our proposed technique is equal to the reliability of consensus recovery block technique. The improvement of performance is based on multi-core architecture where each version of software key units is executed by one core. As a result, by parallel execution of versions, execution time is reduced and performance is improved. Manuscript profile -
Open Access Article
2 - Analysis of Imperfect Space Channel for the Next Generation Satellite Networks
pedram hajipour ali shahzadiAn efficient space data management is imperative in guaranteeing the best performance with a fair distribution of next generation satellite networks. Therefore, one of the major challenges of implementing this kind of future satellite networks is evaluation any untruste MoreAn efficient space data management is imperative in guaranteeing the best performance with a fair distribution of next generation satellite networks. Therefore, one of the major challenges of implementing this kind of future satellite networks is evaluation any untrusted error for the best Quality of Service (QoS). Therefore, Bit Error Rate (BER) criteria based on the type of space channel which it can be defined prefect or imperfect state between satellites and ground stations seems to be a major challenge for space communication. In this paper, the authors provide a bandwidth sharing algorithm for a proposed future satellite networks under multi-beam prototype. This structure has many antennas in transmitter and receiver sides (satellite and ground stations) which they will be communication together based on space data. Using the above framework, the coverage probability and MIMO capacity for a typical multi-beam satellite system is compared with a single antenna for satellite and multi-antenna for area side coverage based on input parameters such as path loss and Signal to Noise Ratio (SNR), respectively. Finally, the bit error rate based on imperfect channel estimation is obtained by employing 4-QAM and QPSK digital modulations and the number of antennas followed by a comparative analysis. Manuscript profile