تخصیص بهینه توان در شبکه رادیوشناختی ‌ با ارسال داده‌ی مستقیم و به کمک رله با راهبرد تقویت و گسیل

نوع مقاله: مقاله پژوهشی

نویسندگان

1 کارشناس ارشد - دانشکده مهندسی برق، واحد نجف آباد، دانشگاه آزاد اسلامی، نجف‌آباد، ایران

2 استادیار - دانشکده مهندسی برق، واحد نجف آباد، دانشگاه آزاد اسلامی، نجف‌آباد، اصفهان، ایران

چکیده

در شبکه های رادیوشناختی، کاربرهای شناختگر امکان استفاده از طیف های مجوزدار، که به کاربران اولیه تخصیص داده شده است را دارند. ولی با توجه به اینکه کاربران اولیه در دسترسی به طیف اولویت دارند، کاربران شناختگر نباید برای آن‌ها تداخل مخرب تولید کنند. در جهت رسیدن به این هدف، تخصیص توان ارسالی کاربرهای شناختگر مسئله ای مهم است. در این مقاله ما تخصیص بهینه توان برای دست یابی به بیشترین نرخ انتقال داده در یک شبکه رادیوشناختی دو کاربره ‌ با ارسال داده‌ی مستقیم و به کمک رله با راهبرد تقویت و گسیل را بررسی می‌کنیم. ابتدا مسئله حداکثر نرخ مجموع را با توجه به محدودیت های تداخل با شبکه اولیه بررسی می‌کنیم، سپس مسئله را از نظر ریاضی تحلیل می‌کنیم. شبیه سازی مسئله تخصیص توان بهینه را براساس مکان‌های مختلف قرار گرفتن رله و مکان های مختلف قرار گرفتن شبکه ی اولیه انجام داده ایم. همچنین نتایج حالت تخصیص بهینه با حالت تخصیص توان مساوی مقایسه شده است.

کلیدواژه‌ها


عنوان مقاله [English]

Optimal Power Allocation for CR Networks with Direct and AF Relay-Aided Transmissions

نویسندگان [English]

  • anahita Pakdelian 1
  • Rouhollah Aghajani 2
1 Msc – Department of Electrical Engineering, Islamic Azad University, Najafabad Branch, Najafabad, Isfahan, Iran
2 Assistant Professor - Department of Electrical Engineering, Islamic Azad University, Najafabad Branch, Najafabad, Isfahan, Iran
چکیده [English]

One of the most prominent challenges in meeting the demand is the scarcity of radio resources. Cognitive radio is one of the techniques has been proposed for efficiently utilizing the radio resources. In Cognitive Radio CR) networks, the CR users have opportunities to access the licensed spectrum bands assigned to the primary users (PUs). Since the PUs have priorities to use the bands, the CR users are not allowed to generate unacceptable interference to them. In this paper, we investigate power allocation schemes for CR networks with two users where one users uses direct transmission and the other uses AF relay-aided transmissions. We first formulate an overall rate optimization problem with interference constraints to the PU and peak power constraints at each node and obtain solutions by theoretical analysis. We also simulate the solution base on different location of the relay and different location of the PU network.we compare the results with equal power allocation

کلیدواژه‌ها [English]

  • Cognitive Radio Networks
  • Optimum power allocation
  • Interference Constraints
  • Direct transmission
  • Amplify and forward
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