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- Type of Document: M.Sc. Thesis
- Language: Farsi
- Document No: 40779 (05)
- University: Sharif University of Technology
- Department: Electrical Engineering
- Advisor(s): Hossein Khalaj, Babak; Behnia, Fereidoon
- Abstract:
- In this work we have investigated the methods of providing quality of service in cognitive radio networks. At first, we have explained the various algorithms of providing BER quality of service in wireless networks. Especially we have explained those algorithms which are known as the distributed power control algorithms. Then we have introduced methods of using adaptive modulation and we have used this kind of modulation to provide delay quality of service in cognitive radio networks. We have done this by maximizing the sum of effective capacities of secondary links under the power constraints and also the interference constraints set by the primary receivers. Finally, we have introduced several methods for synchronous delay and BER quality of service provisioning. One of these methods is a distributed algorithm and therefore it can be a practical method. This method is based on an innovative algorithm which stochastically turns off some of the secondary transmitters who are transmitting with high powers and thus violating the interference constraints. In this algorithm, a probability proportional to the transmission power and the channel gains is assigned to each secondary transmitter and the transmitter should turn off its transmission with that probability.
- Keywords:
- Service Quality ; Distributed Algorithm ; Cognitive Radio ; Adaptive Modulation ; Power Control
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- فهرست مطالب
- لیست تصاویر
- مقدمه و تعریف کیفیت سرویس
- فراهمسازی کیفیت سرویس با معیار احتمال خطا در شبکهها
- فراهم سازی کیفیت سرویس با معیار تاخیر در شبکه های رادیوی شناختی
- فراهمسازی همزمان کیفیت سرویس با معیارهای احتمال خطا و تاخیر
- نتیجه گیری و پیشنهادات
- مراجع
- واژهنامه فارسی به انگلیسی
- واژهنامه انگلیسی به فارسی