【摘 要】
：
We formulate the subcarrier and power allocation problem in cognitive radio networks employing orthogonal frequency division multiplexing (OFDM) as a non-linear
【机 构】
：
Key Laboratory of Universal Wireless Communications
【基金项目】
：
国家自然科学基金;the National High Technology Research and Development Programme of China
论文部分内容阅读
We formulate the subcarrier and power allocation problem in cognitive radio networks employing orthogonal frequency division multiplexing (OFDM) as a non-linear optimization problem with the objective of maximizing sum capacity under constraints of available subcarriers, interference temper- ature, power budget, etc. A close-to-optimal solution with much reduced complexity is proposed to separate the problem into two steps, which also considers fairness among secondary users. A fair al- gorithm for subcarrier allocation (FA_SA) is firstly presented. Secondly, a fast iterative water-filling algorithm for power allocation (FIWFA_PA) is also proposed to maximize the sum capacity. Exten- sive simulation results show that sum capacity performance of our low-complexity solution is very close to the optimal one, while significantly improving fairness and reducing computation complexity compared with the existing solutions.
其他文献
In this paper, a network scenario of two-way relaying over orthogonal frequency division multiplexing (OFDM) is considered,in which two nodes intend to exchange
High pressure is an important development orientation in pneumatic field,since it can not only improve dynamic characteristics of pneumatic system but also decr
What is pursued by multi-product type and variant volume(MPTVV) production is rapid response and quick switching, so that structure of transferring line in manu
Electro-hydraulic screw down servo system(HSDS)is widely used in seamless tube rolling mill in western companies.But in Chinese companies,mechanical screw down
The nano-MoS2 particles were adopted to substitute for the extreme-pressure and anti-wear additives to the rolling fluid for steel strips. An optimal formulatio
Reduction of drag torque is one of important potentials to improve transmission efficiency. Existing mathematical model of drag torque was not accurate to predi
There are very few researches on the shape standard curve currently,and they merely remain on the level of description of the general concept and production exp
High strength compacted graphite iron (CGI) or alloyed cast iron components are substituting previously used non-ferrous castings in automotive power train appl
A polyether diol poly[3 -bromomethyl-3 -tridecafluorooc-tyloxymethyloxetane]glycol ( PFBOX 3) was prepared in 91% yield from ring opening polymerization of 3 -b