In this paper, proportional fairness(PF)-based energy-efficient power allocation is studied for multiple-input multiple-output(MIMO) non-orthogonal multiple access(NOMA) systems. In our schemes, statistical channel st...In this paper, proportional fairness(PF)-based energy-efficient power allocation is studied for multiple-input multiple-output(MIMO) non-orthogonal multiple access(NOMA) systems. In our schemes, statistical channel state information(CSI) is utilized for perfect CSI is impossible to achieve in practice. PF is used to balance the transmission efficiency and user fairness. Energy efficiency(EE) is formulated under basic data rate requirements and maximum transmitting power constraints. Due to the non-convex nature of EE, a two-step algorithm is proposed to obtain sub-optimal solution with a low complexity. Firstly, power allocation is determined by golden section search for fixed power. Secondly total transmitting power is determined by fractional programming method in the feasible regions. Compared to the performance of MIMO-NOMA without PF constraint, fairness is obtained at expense of decreasing of EE.展开更多
With the rapid evolution of Internet of things(IoT),many edge devices require simultaneous connection in 5G communication era.To afford massive data of IoT devices,multiple input multiple output non-orthogonal multipl...With the rapid evolution of Internet of things(IoT),many edge devices require simultaneous connection in 5G communication era.To afford massive data of IoT devices,multiple input multiple output non-orthogonal multiple access(MIMO-NOMA)method has been considered as a promising technology.However,there are numerous drawbacks due to error propagation and inter-user interferences.Therefore,proposed scheme aims to improve the reliability of the MIMO-NOMA system with digital beamforming and intracluster cooperative multi point(CoMP)to efficiently support IoT system.In the conventional MIMO-NOMA system,user entities are grouped into clusters.Block diagonalization(BD)is applied to efficiently eliminate the inter-cluster interference of the MIMO-NOMA system.However,since the channel path of the data stream from a single antenna to a single cluster doesn’t hold other cluster’s data,the system can’t fully utilize the selective subcarrier channel states.It indicates that there can be better channel paths for a data stream at a certain subcarrier index.Therefore,proposed scheme allocates data streams to antennas adaptively considering selective channel states.Additionally,intra-cluster CoMP method is adjusted to enhance the reliability of the system in the clusters.The simulation results show that the proposed scheme improves BER and throughput performance compared to the conventional MIMO-NOMA system.展开更多
One of the most important methods used to cope with multipath fading effects,which cause the symbol to be received incorrectly in wireless communication systems,is the use of multiple transceiver antenna structures.By...One of the most important methods used to cope with multipath fading effects,which cause the symbol to be received incorrectly in wireless communication systems,is the use of multiple transceiver antenna structures.By combining the multi-input multi-output(MIMO)antenna structure with non-orthogonal multiple access(NOMA),which is a new multiplexing method,the fading effects of the channels are not only reduced but also high data rate transmission is ensured.However,when the maximum likelihood(ML)algorithm that has high performance on coherent detection,is used as a symbol detector in MIMO NOMA systems,the computational complexity of the system increases due to higher-order constellations and antenna sizes.As a result,the implementation of this algorithm will be impractical.In this study,the backtracking search algorithm(BSA)is proposed to reduce the computational complexity of the symbol detection and have a good bit error performance for MIMO-NOMA systems.To emphasize the efficiency of the proposed algorithm,simulations have been made for the system with various antenna sizes.As can be seen from the obtained results,a considerable reduction in complexity has occurred using BSA compared to the ML algorithm,also the bit error performance of the system is increased compared to other algorithms.展开更多
为了满足未来高容量通信的需求,在太赫兹波段进行通信受到了学术界和工业界的关注。多输入多输出(Multiple-Input Multiple-Output,MIMO)技术和非正交多址(Non-Orthgonal Multiple Access,NOMA)技术可以使太赫兹通信网络承载更多的用户...为了满足未来高容量通信的需求,在太赫兹波段进行通信受到了学术界和工业界的关注。多输入多输出(Multiple-Input Multiple-Output,MIMO)技术和非正交多址(Non-Orthgonal Multiple Access,NOMA)技术可以使太赫兹通信网络承载更多的用户,提高系统的能量效率。由于无线设备电池容量有限,电能的供给对通信技术的发展也至关重要。当基站成功完成数据传输后,无线信号的能量通常会被当作无用功率而浪费。通过将无线携能通信(Simultaneous Wireless Information and Power Transfer,SWIPT)技术应用于太赫兹通信网络,有助于减少能耗,提高系统的能量效率。重点分析了MIMO技术、NOMA技术以及SWIPT技术在太赫兹通信系统中的应用及其目前所面临的挑战,以供参考。展开更多
基金supported by the National Natural Science Foundation of China (No. 61671252)
文摘In this paper, proportional fairness(PF)-based energy-efficient power allocation is studied for multiple-input multiple-output(MIMO) non-orthogonal multiple access(NOMA) systems. In our schemes, statistical channel state information(CSI) is utilized for perfect CSI is impossible to achieve in practice. PF is used to balance the transmission efficiency and user fairness. Energy efficiency(EE) is formulated under basic data rate requirements and maximum transmitting power constraints. Due to the non-convex nature of EE, a two-step algorithm is proposed to obtain sub-optimal solution with a low complexity. Firstly, power allocation is determined by golden section search for fixed power. Secondly total transmitting power is determined by fractional programming method in the feasible regions. Compared to the performance of MIMO-NOMA without PF constraint, fairness is obtained at expense of decreasing of EE.
基金This research was supported by Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(2020R1A6A1A 03038540)was supported by Institute for Information&communications Technology Promotion(IITP)grant funded by the Korea government(MSIT)(No.2017-0-00217,Development of Immersive Signage Based on Variable Transparency and Multiple Layers)。
文摘With the rapid evolution of Internet of things(IoT),many edge devices require simultaneous connection in 5G communication era.To afford massive data of IoT devices,multiple input multiple output non-orthogonal multiple access(MIMO-NOMA)method has been considered as a promising technology.However,there are numerous drawbacks due to error propagation and inter-user interferences.Therefore,proposed scheme aims to improve the reliability of the MIMO-NOMA system with digital beamforming and intracluster cooperative multi point(CoMP)to efficiently support IoT system.In the conventional MIMO-NOMA system,user entities are grouped into clusters.Block diagonalization(BD)is applied to efficiently eliminate the inter-cluster interference of the MIMO-NOMA system.However,since the channel path of the data stream from a single antenna to a single cluster doesn’t hold other cluster’s data,the system can’t fully utilize the selective subcarrier channel states.It indicates that there can be better channel paths for a data stream at a certain subcarrier index.Therefore,proposed scheme allocates data streams to antennas adaptively considering selective channel states.Additionally,intra-cluster CoMP method is adjusted to enhance the reliability of the system in the clusters.The simulation results show that the proposed scheme improves BER and throughput performance compared to the conventional MIMO-NOMA system.
基金supported by the Scientific Research Projects Coordination Unit of Bandirma Onyedi Eylül University.Project Number BAP-19-MF-1004-005.
文摘One of the most important methods used to cope with multipath fading effects,which cause the symbol to be received incorrectly in wireless communication systems,is the use of multiple transceiver antenna structures.By combining the multi-input multi-output(MIMO)antenna structure with non-orthogonal multiple access(NOMA),which is a new multiplexing method,the fading effects of the channels are not only reduced but also high data rate transmission is ensured.However,when the maximum likelihood(ML)algorithm that has high performance on coherent detection,is used as a symbol detector in MIMO NOMA systems,the computational complexity of the system increases due to higher-order constellations and antenna sizes.As a result,the implementation of this algorithm will be impractical.In this study,the backtracking search algorithm(BSA)is proposed to reduce the computational complexity of the symbol detection and have a good bit error performance for MIMO-NOMA systems.To emphasize the efficiency of the proposed algorithm,simulations have been made for the system with various antenna sizes.As can be seen from the obtained results,a considerable reduction in complexity has occurred using BSA compared to the ML algorithm,also the bit error performance of the system is increased compared to other algorithms.
文摘为了满足未来高容量通信的需求,在太赫兹波段进行通信受到了学术界和工业界的关注。多输入多输出(Multiple-Input Multiple-Output,MIMO)技术和非正交多址(Non-Orthgonal Multiple Access,NOMA)技术可以使太赫兹通信网络承载更多的用户,提高系统的能量效率。由于无线设备电池容量有限,电能的供给对通信技术的发展也至关重要。当基站成功完成数据传输后,无线信号的能量通常会被当作无用功率而浪费。通过将无线携能通信(Simultaneous Wireless Information and Power Transfer,SWIPT)技术应用于太赫兹通信网络,有助于减少能耗,提高系统的能量效率。重点分析了MIMO技术、NOMA技术以及SWIPT技术在太赫兹通信系统中的应用及其目前所面临的挑战,以供参考。
