该文分析了功率约束条件下MIMO-OFDM系统广播信道的发送优化问题,提出了两种不同准则下的多用户传输策略和功率分配方案,即最优空间距离OSD-DPC(Optimal Space Distance Dirty Paper Coding)方案和最大化信噪比波束成形MSNR-DPC(Max Sig...该文分析了功率约束条件下MIMO-OFDM系统广播信道的发送优化问题,提出了两种不同准则下的多用户传输策略和功率分配方案,即最优空间距离OSD-DPC(Optimal Space Distance Dirty Paper Coding)方案和最大化信噪比波束成形MSNR-DPC(Max Signal to Noise Ratio Dirty Paper Coding)方案。数据结果表明,两种传输策略与理论上的最优传输方案性能非常接近,可以显著提高功率约束条件下的系统性能与容量。展开更多
This paper studies the cognitive broadcast channel in which the primary user communicates to the primary receiver, while the secondary user has noncausal knowledge of the primary radio's codeword and expects to co...This paper studies the cognitive broadcast channel in which the primary user communicates to the primary receiver, while the secondary user has noncausal knowledge of the primary radio's codeword and expects to communicate to two secondary receivers. Comparing with the existing cognitive radio channel which considers only one secondary receiver, cognitive broadcast channel studies the case that there are multiple secondary receivers.To this end, we investigate the fundamental limits of the performance of the Gaussian cognitive broadcast channel from the information theoretic perspective. Specifically, we derive the capacity region of the Gaussian cognitive degraded broadcast channel with weak interference.展开更多
Orthogonal Frequency Division Multiplexing(OFDM) is an effective technique to deal with a frequency selective channel since it can convert the channel into some flat fading subchannels.However,very different output SN...Orthogonal Frequency Division Multiplexing(OFDM) is an effective technique to deal with a frequency selective channel since it can convert the channel into some flat fading subchannels.However,very different output SNR values of the subchannels will lead to poor bit error performance when a linear equalizer and Equal Bit Allocation(EBA) are adopted in OFDM systems.So,we proposed three novel nonlinear Joint Transceiver(JT) schemes based on Zero-Forcing(ZF) criterion and Minimum Mean Square Error(MMSE) criterion respectively,which can transform all subchannels of an OFDM system into subchannels with identical channel gain.Thus,EBA is equivalent to the Optimum Bit Allocation(OBA) for these subchannels.Numerical analysis helps us to obtain the theoretical approximate BER values of the JT scheme.Simulation results verify the numerical analysis and confirm that the performance of our proposed JT scheme greatly outperforms the traditional linear equalizer with EBA at moderate and high SNR values.展开更多
文摘该文分析了功率约束条件下MIMO-OFDM系统广播信道的发送优化问题,提出了两种不同准则下的多用户传输策略和功率分配方案,即最优空间距离OSD-DPC(Optimal Space Distance Dirty Paper Coding)方案和最大化信噪比波束成形MSNR-DPC(Max Signal to Noise Ratio Dirty Paper Coding)方案。数据结果表明,两种传输策略与理论上的最优传输方案性能非常接近,可以显著提高功率约束条件下的系统性能与容量。
基金supported by the Project-Sponsored by SRF for ROCS,SEMthe National Science and Technology Major Project of the Ministry of Science and Technologyof China under Grants No.2012ZX03003004,No.2010ZX03006002+2 种基金the National Natural Science Foundation of China under Grants No.61172052,No.61261046the Scientific Research Foundation of the Higher Education Institutions of Guangxi under Grant No.201203YB159Wuzhou University Foundation under Grant No.2012B001
文摘This paper studies the cognitive broadcast channel in which the primary user communicates to the primary receiver, while the secondary user has noncausal knowledge of the primary radio's codeword and expects to communicate to two secondary receivers. Comparing with the existing cognitive radio channel which considers only one secondary receiver, cognitive broadcast channel studies the case that there are multiple secondary receivers.To this end, we investigate the fundamental limits of the performance of the Gaussian cognitive broadcast channel from the information theoretic perspective. Specifically, we derive the capacity region of the Gaussian cognitive degraded broadcast channel with weak interference.
基金the National Natural Science Foundation of China for Distinguished Young Scholars，the National Key Basic Research Program of China (973 program)，the National Natural Science Foundation of China，the National Science and Technology Major Project，the Special Research Fund of State Key Laboratory，the 111 Project
文摘Orthogonal Frequency Division Multiplexing(OFDM) is an effective technique to deal with a frequency selective channel since it can convert the channel into some flat fading subchannels.However,very different output SNR values of the subchannels will lead to poor bit error performance when a linear equalizer and Equal Bit Allocation(EBA) are adopted in OFDM systems.So,we proposed three novel nonlinear Joint Transceiver(JT) schemes based on Zero-Forcing(ZF) criterion and Minimum Mean Square Error(MMSE) criterion respectively,which can transform all subchannels of an OFDM system into subchannels with identical channel gain.Thus,EBA is equivalent to the Optimum Bit Allocation(OBA) for these subchannels.Numerical analysis helps us to obtain the theoretical approximate BER values of the JT scheme.Simulation results verify the numerical analysis and confirm that the performance of our proposed JT scheme greatly outperforms the traditional linear equalizer with EBA at moderate and high SNR values.
