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GLOBECOM
2008
IEEE

Power Allocation for Cognitive Radios Based on Primary User Activity in an OFDM System

13 years 12 months ago
Power Allocation for Cognitive Radios Based on Primary User Activity in an OFDM System
Efficient and reliable power allocation algorithm in Cognitive radio (CR) networks is a challenging problem. Traditional water-filling algorithm is inefficient for CR networks due to the interaction with primary users. In this paper, we consider reliability/availability of subcarriers or primary user activity for power allocation. We model this aspect mathematically with a risk-return model by defining a general rate loss function. We then propose optimal and suboptimal algorithms to allocate power under a fixed power budget for such a system with linear rate loss. These algorithms as we will see allocate more power to more reliable subcarriers in a water-filling fashion with different water levels. We compare the performance of these algorithms for our model with respect to water-filling solutions. Simulations show that suboptimal schemes perform closer to optimal scheme although they could be implemented with same complexity as water-filling algorithm. Finally, we discuss the lineari...
Ziaul Hasan, Ekram Hossain, Charles L. Despins, Vi
Added 07 Dec 2010
Updated 07 Dec 2010
Type Conference
Year 2008
Where GLOBECOM
Authors Ziaul Hasan, Ekram Hossain, Charles L. Despins, Vijay K. Bhargava
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