This paper investigates the relay selection and resource allocation problem in multiuser orthogonal frequency division multiplexing (OFDM) based cooperative cellular networks, in which user nodes could relay informa...This paper investigates the relay selection and resource allocation problem in multiuser orthogonal frequency division multiplexing (OFDM) based cooperative cellular networks, in which user nodes could relay information for each other using the decode-and-forward (DF) protocol to achieve spatial diversity gain. Specifically, the paper proposes an optimal joint relay selection and resource allocation (0RSRA) algorithm whose objective is to maximize system total achievable data rate with the constraints of each user' s individual quality of service (QoS) requirement and transmission power. Due to being a mixed binary integer programming (MBIP) problem, a novel two-level Lagrangian dual-primal decomposition and subgradient projection approach is proposed to not only select the appropriate cooperative relay nodes, but also allocate subcarries and power optimally. Simulation re- suits demonstrate that our proposed scheme can efficiently enhance overall system data rate and guarantee each user' s QoS requirement. Meanwhile, the fairness among users can be improved dramatically.展开更多
Physical-layer network coding(PNC) promises substantial theoretical gain to achieve the maximum system throughput in cooperative relay transmission. However, with the increasing global warming, how to reduce power con...Physical-layer network coding(PNC) promises substantial theoretical gain to achieve the maximum system throughput in cooperative relay transmission. However, with the increasing global warming, how to reduce power consumption while satisfy system throughput requirement is becoming a vital issue. In this paper, we investigate energy-efficiency resource allocation(RA) based on PNC with amplify-and-forward(AF) protocol in orthogonal frequency division multiple(OFDM) bidirectional transmission. To minimize the overall transmit power consumption with required system throughput requirement, we consider joint subcarriers and power allocation and formulate the objective task into a constrained optimization problem where the best relay node is selected to minimize total transmit power. The closed form optimization power allocation solutions are acquired by analytical derivation. Based on derivation, we propose a novel optimal energy-efficient power allocation(OE-PA). Numerical results are given to evaluate the performance of the derived scheme as compared to other schemes and show that our scheme has signifi cant improvement to energy saving.展开更多
基金Supported by the National Natural Science Foundation for Distinguished Young Scholar ( No. 61001115 ) and the Beijing Municipal Natural Science Foundation ( No. 4102044).
文摘This paper investigates the relay selection and resource allocation problem in multiuser orthogonal frequency division multiplexing (OFDM) based cooperative cellular networks, in which user nodes could relay information for each other using the decode-and-forward (DF) protocol to achieve spatial diversity gain. Specifically, the paper proposes an optimal joint relay selection and resource allocation (0RSRA) algorithm whose objective is to maximize system total achievable data rate with the constraints of each user' s individual quality of service (QoS) requirement and transmission power. Due to being a mixed binary integer programming (MBIP) problem, a novel two-level Lagrangian dual-primal decomposition and subgradient projection approach is proposed to not only select the appropriate cooperative relay nodes, but also allocate subcarries and power optimally. Simulation re- suits demonstrate that our proposed scheme can efficiently enhance overall system data rate and guarantee each user' s QoS requirement. Meanwhile, the fairness among users can be improved dramatically.
基金supported by the Science Instrument Special Funds of the National Natural Science Foundation of China under Grant No.61027003the National High Technology Research and Development Program of China under Grant No.2012AA01A50604
文摘Physical-layer network coding(PNC) promises substantial theoretical gain to achieve the maximum system throughput in cooperative relay transmission. However, with the increasing global warming, how to reduce power consumption while satisfy system throughput requirement is becoming a vital issue. In this paper, we investigate energy-efficiency resource allocation(RA) based on PNC with amplify-and-forward(AF) protocol in orthogonal frequency division multiple(OFDM) bidirectional transmission. To minimize the overall transmit power consumption with required system throughput requirement, we consider joint subcarriers and power allocation and formulate the objective task into a constrained optimization problem where the best relay node is selected to minimize total transmit power. The closed form optimization power allocation solutions are acquired by analytical derivation. Based on derivation, we propose a novel optimal energy-efficient power allocation(OE-PA). Numerical results are given to evaluate the performance of the derived scheme as compared to other schemes and show that our scheme has signifi cant improvement to energy saving.