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“卫星中频分配网络”模式建设中须注意的问题
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作者 金军 张毅 《西部广播电视》 2005年第12期50-51,共2页
本文介绍中频分配网络建设中须注意的几个问题,并在实际应用中如何解决。
关键词 中频分配 卫星接收
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65米射电望远镜中频传输分配系统的研制 被引量:1
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作者 袁瑾 苟伟 +1 位作者 赵融冰 李斌 《天文研究与技术》 CSCD 2015年第3期262-269,共8页
设计和实现了65m射电望远镜中频传输分配系统,频率范围0.1~2.5GHz,通道数6路,0~30dB衰减本地和远程可调,链路增益、端口驻波比、分配输出隔离度、通道一致性等指标满足要求,给数字终端提供了良好的中频输入信号。经过系统验证... 设计和实现了65m射电望远镜中频传输分配系统,频率范围0.1~2.5GHz,通道数6路,0~30dB衰减本地和远程可调,链路增益、端口驻波比、分配输出隔离度、通道一致性等指标满足要求,给数字终端提供了良好的中频输入信号。经过系统验证,该中频传输分配系统整体性能优良。可以很好地满足射电观测的需求。 展开更多
关键词 射电望远镜 中频传输链路 宽带均衡 中频分配 衰减控制
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Optimal joint relay selection and resource allocation with QoS constraints in multiuser OFDM-based cellular networks 被引量:2
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作者 Chen Dan Ji Hong Li Xi Luo Changqing 《High Technology Letters》 EI CAS 2011年第3期305-310,共6页
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
关键词 cooperative diversity relay selection resource allocation Lagrangian dual-primal decomposition
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Joint Subcarrier and Power Allocation for DF-Based Multiuser Two-Way Relay Networks
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作者 Xiang Chen Fei He +1 位作者 Limin Xiao Shidong Zhou 《China Communications》 SCIE CSCD 2017年第6期179-188,共10页
Two-way decode-and-forward(DF) relay technique is an efficient method to improve system performance in 5G networks.However,traditional orthogonal frequency division multiplexing(OFDM) based two-way relay systems only ... Two-way decode-and-forward(DF) relay technique is an efficient method to improve system performance in 5G networks.However,traditional orthogonal frequency division multiplexing(OFDM) based two-way relay systems only consider a per-subcarrier relay strategy,which treats each subcarrier as a separate channel,which results in significant sum rate loss,especially in fading environments.In this paper,a joint coding scheme over multiple subcarriers is involved for multipair users in two-way relay systems to obtain multiuser diversity.A generalized subcarrier pairing strategy is proposed to permit each user-pair to occupy different subcarriers during the two transmission phases,i.e.,the multiple access and broadcast phases.Moreover,a low complexity joint resource allocation scheme is proposed to improve the spectrum efficiency with an additional multi-user diversity gain.Some numerical simulations are finally provided to verify the efficacy of our proposal. 展开更多
关键词 two-way relay orthogonal frequency division multiplexing (OFDM) decode-and-forward (DF) power allocation
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