Seyed Mohsen Eghbali ¹, Iman Beiranvand ¹

Affiliations
1 Department of Electrical and Computer Engineering, Eyvanekey Institute of Higher Education (Nongovernmental–Nonprofit), Semnan, IR

Abstract

Objectives: Using the imperialist competitive algorithm (ICA) for finding the optimal values of the phase in PTS method in order to Peak-to-average power ratio reduction. Methods/Analysis: In order to PAPR reduction we have used a numerical method to calculate the Bose–Einstein equations that appear in efficiency of solar cells. Findings: The proposed method reduces the PAPR more than other methods and also does not lead to an increase in BER. PAPR is reduced the amount of 3.97 dB that is equal to 34.75% of initial value of PAPR. Also by increasing the subcarrier amount of these reductions are increased but required to increasing in compute the increase and cost. Novelty of the Study: For the first time, imperialist competitive algorithm (ICA) is used for finding the optimal values of the phase in Partial Transmit Sequence (PTS) method. Conclusion/Application: One of the most important applications of the results of this study is the satellite communication system. Also, PAPR reduction will be reduced operating costs dramatically.

Keywords

ICA Algorithm, PAPR Reduction, PTS OFDM Scheme, Satellite Communication

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Shahram Mohammadnejad ¹, Iman Beiranvand ¹

Affiliations
1 Nanoptronics Research Center, Department of Electrical and Electronics Engineering, Iran University of Science and Technology, Tehran,, IR

Abstract

Nowadays silicon crystalline solar cell efficiency has reached about 25%. Quantum dot solar cells can considerably increase the cell’s efficiency. The underlying concept of hot carrier solar cells is slowing the rate of photo-excited carrier cooling that is made by phonon interaction in the lattice and allowing much time for the carriers to be collected until they are still at elevated energies. In this condition higher cell voltage can be achieved and also the total efficiency of solar cell has increased. In this paper the affective parameters on the efficiency and performance of the hot carrier solar cell has been investigated. The results show that if the size of quantum dots be 8 times their total energy has reduced 5 times. Also by using quantum dots in cell’s contact the efficiency could be increased to 81%. If the temperature of the hot carriers 25 percent increases, the cell efficiency increases to 60 percent. As well as 100 degree rise up in temperature, is caused efficiency decreases till 2 percent. This results shows that the cell is not sensitive to changes in ambient temperature. According to cell efficiency variation based on band gap, using InN and Ge quantum dots in the cell’s contacts is proposed.

Keywords

Hot Carrier Solar Cells, Selective Energy Contact, Phonon, Quantum Dot.

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