دانلود رایگان مقاله انگلیسی تخصیص منابع ضد سایه برای شبکه های رادیوشناختی سیار عمومی - نشریه IEEE

ABSTRACT

Resource allocation (RA) for mobile secondary users (SUs) is considered one of the most important techniques for designing the next-generation cognitive radio network (CRN). In this paper, ‘effective capacity (EC)’ is proposed to improve the RA performance for an underlay-based mobile CRN. By optimizing EC, an efficient resource allocation scheme is developed. First, we consider a moving secondary system where the channel state information (CSI) can be predicted by location-awareness techniques. According to the prediction result, we set protecting parameters for both the secondary and the primary performance targets to minimize the prediction error introduced by the decorrelated shadowing. Second, the computed sum average EC of the cognitive system is maximized. To solve the optimization RA problem, a low-complexity stepwise algorithm is proposed based on four procedures aimed at access, initialization, subchannel and power. Moreover, the speeds of the primary users (PUs) are taken into account, and a general system model is built. The corresponding resource allocation solutions can be induced easily through extending the originally proposed solution. Finally, simulation results are provided to confirm the EC based algorithm. The proposed approach can not only improve the total secondary capacity but also achieve higher energy efficiency (EE) and spectrum efficiency (SE) for the mobile secondary system.

VII. Conclusion

In this paper, we presented an anti-shadowing subchannel and power resource allocation method for OFDMA-based mobile SUs in cellular CRNs, aiming at maximization of the total secondary effective capacity. Considering the diversity of locations and channel conditions for the mobile SUs, an anti-shadowing CSI prediction method was proposed. A stepwise resource allocation algorithm with low complexity was introduced to make the problem tractable. Using this original algorithm, extension schemes could be deduced similarly for the general mobile CRNs with moving PUs. Compared with some previous schemes, the simulation results revealed the relationships between the secondary performances and various system parameters. Moreover, the benefits of our original scheme were verified in terms of the effective capacity, energy efficiency and spectrum efficiency.