This paper describes an optimal power allocation scheme for orthogonal frequency division multiple access two-way relay networks with physical network coding. The aim is to enhance the achievable sum rate of the termi...This paper describes an optimal power allocation scheme for orthogonal frequency division multiple access two-way relay networks with physical network coding. The aim is to enhance the achievable sum rate of the terminals for a constrained total transmit power. Convex optimization is used to derive a closed-form solution for the power allocation between the relay node and the two terminals. This reduces the variable dimensionality of the objective function for the power assignment problem among multiple carriers when the total transmit power is constrained. This solution is then used to derive the optimal power control scheme. This method reduces the implementation complexity compared with the traditional resource allocation scheme. Numerical and simulation results show that the approach achieves almost the optimal sum rate and outperforms the fixed power assignment method with less computational load in various scenarios.展开更多
This article considers the two-way multiple-input multiple-output(MIMO) relaying channels with multiple users,in which multiple users are served simultaneously by the base station(BS) with the assistance of the re...This article considers the two-way multiple-input multiple-output(MIMO) relaying channels with multiple users,in which multiple users are served simultaneously by the base station(BS) with the assistance of the relay.The transmission consists of only two phases,doubling the system throughout over traditional one-way half-duplex transmission.A zero-forcing dirty paper coding(ZFDPC) aided physical-layer network coding(PNC) scheme is proposed in this article and the achievable capacity of the ZFDPC aided PNC scheme is derived.Simulation results show that the proposed scheme outperforms the previous decode-and-forward(DF) and zero-forcing beamforming(ZFBF) aided PNC scheme due to more degrees of freedoms and the advantage of PNC.Moreover,we analyze the effect of the imperfect channel state information(CSI) from RS to users at BS side to show the robustness of the proposed ZFDPC aided PNC scheme.展开更多
This study analyzes the impact of Physical-layer Network Coding (PNC) on the throughput of a large random wireless network, including one-dimensional and two-dimensional networks. Three different transmission scheme...This study analyzes the impact of Physical-layer Network Coding (PNC) on the throughput of a large random wireless network, including one-dimensional and two-dimensional networks. Three different transmission schemes, (1) a traditional flow-based scheme, (2) a network coding scheme, and (3) the PNC scheme are compared to show that the PNC scheme improves wireless network throughput by a constant factor without changing the scaling law compared to the traditional flow-based and network coding schemes. Furthermore, PNC can reduce the effect of interference for the one-dimensional networks, and has a tighter throughput bound for the two-dimensional network.展开更多
基金Supported by the Fundamental Research Funds for the Central Universities (No. K50510010027)
文摘This paper describes an optimal power allocation scheme for orthogonal frequency division multiple access two-way relay networks with physical network coding. The aim is to enhance the achievable sum rate of the terminals for a constrained total transmit power. Convex optimization is used to derive a closed-form solution for the power allocation between the relay node and the two terminals. This reduces the variable dimensionality of the objective function for the power assignment problem among multiple carriers when the total transmit power is constrained. This solution is then used to derive the optimal power control scheme. This method reduces the implementation complexity compared with the traditional resource allocation scheme. Numerical and simulation results show that the approach achieves almost the optimal sum rate and outperforms the fixed power assignment method with less computational load in various scenarios.
基金supported by IMT-Advanced Novel Wireless Transmission Technology Program (2008ZX03003-004,2008BAH30B09)Chinese Important National Science and Technology Specific Project (2010ZX03002-003)+1 种基金the National Basic Research Program of China (2007CB310602)International Science and Technology Cooperation Program (2008DFA12160)
文摘This article considers the two-way multiple-input multiple-output(MIMO) relaying channels with multiple users,in which multiple users are served simultaneously by the base station(BS) with the assistance of the relay.The transmission consists of only two phases,doubling the system throughout over traditional one-way half-duplex transmission.A zero-forcing dirty paper coding(ZFDPC) aided physical-layer network coding(PNC) scheme is proposed in this article and the achievable capacity of the ZFDPC aided PNC scheme is derived.Simulation results show that the proposed scheme outperforms the previous decode-and-forward(DF) and zero-forcing beamforming(ZFBF) aided PNC scheme due to more degrees of freedoms and the advantage of PNC.Moreover,we analyze the effect of the imperfect channel state information(CSI) from RS to users at BS side to show the robustness of the proposed ZFDPC aided PNC scheme.
文摘This study analyzes the impact of Physical-layer Network Coding (PNC) on the throughput of a large random wireless network, including one-dimensional and two-dimensional networks. Three different transmission schemes, (1) a traditional flow-based scheme, (2) a network coding scheme, and (3) the PNC scheme are compared to show that the PNC scheme improves wireless network throughput by a constant factor without changing the scaling law compared to the traditional flow-based and network coding schemes. Furthermore, PNC can reduce the effect of interference for the one-dimensional networks, and has a tighter throughput bound for the two-dimensional network.