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电子音乐中Fade In及Fade Out效果应用 被引量:1
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作者 潘广宇 《歌海》 2008年第6期26-27,共2页
在电子音乐处理手法多如牛毛的今天,人们对电子音乐审美正随着电子音乐地发展而提高。但劣质CD音乐同时抑制着电子音乐的整体发展,影响人们的音乐审美。因此,本文通过对音乐Fade-In及Fade-Out音频前期制作中的情绪辅助表达、录音过程中... 在电子音乐处理手法多如牛毛的今天,人们对电子音乐审美正随着电子音乐地发展而提高。但劣质CD音乐同时抑制着电子音乐的整体发展,影响人们的音乐审美。因此,本文通过对音乐Fade-In及Fade-Out音频前期制作中的情绪辅助表达、录音过程中的音频剪辑、CD成品刻录中的防止爆破三种作用的研究,力图在尽量保持电子音乐高品质的同时,不断的尝试新的操作构思,为电子音乐地发展创新锦上添花。 展开更多
关键词 fade In及fade out 电子音乐 音频
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无编程和填表制导开发环境FADE
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作者 陈启泉 吴清江 陈维斌 《计算机工程与应用》 CSCD 北大核心 1992年第9期50-55,共6页
本文介绍无编程软件应用系统开发环境FADE的设计思想,论述无编程开发工具的类型和特点,填表式制导开发方式的应用系统的生成过程,并给出了表格数据库的文法和语义描述。
关键词 fade 程序设计
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应用FADE品质改善模式改善新入院病人护理细节质量 被引量:4
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作者 佐小丽 郗君梅 +3 位作者 钟琼 罗丹 余颖 刘莉 《护理学报》 2017年第10期14-16,共3页
目的应用FADE[focus(确认问题);analyze(问题分析,指出需要了解的事项,并收集资料以决定影响因素);develop(建立计划以解决问题);execute(执行改善计划并追综检讨,FADE]品质改善模式,持续改进新入院病人护理细节质量,确保病人安全。方法... 目的应用FADE[focus(确认问题);analyze(问题分析,指出需要了解的事项,并收集资料以决定影响因素);develop(建立计划以解决问题);execute(执行改善计划并追综检讨,FADE]品质改善模式,持续改进新入院病人护理细节质量,确保病人安全。方法 2014年11月—2015年6月应用FADE品质改善模式,确认改进问题为"新入院病人护理细节质量",找出影响新入院病人护理细节质量的主要问题,并针对问题进行根因分析找出影响因素,制定新入院病人护理细节质量标准、改进目标及改进策略,执行计划并追踪检讨持续改进,运用数据评价改进效果。结果实施改进前2014年11月新入院病人护理细节质量合格率为77.9%,实施改进后,2015年1—6月共检查6次,新入院病人护理细节质量平均合格率为92.2%,实施前后合格率比较,差异有统计学意义(P<0.01),有效改进了新入院病人护理工作中存在的问题。结论应用FADE品质改善模式,有效改进了新入院病人护理中存在的问题,提高了新入院病人护理细节质量,确保了病人安全。 展开更多
关键词 fade品质改善模式 新入院病人护理质量 持续改进
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Power Control for Fading Channels in Cognitive Radio Networks with Outage-Probability Minimization 被引量:4
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作者 Luan Yu Li Hongzuo Wang Yafei 《China Communications》 SCIE CSCD 2012年第12期108-116,共9页
Cognitive radio allows Secondary Users (SUs) to dynamically use the spectrum resource licensed to Prirmry Users (PUs), and significantly improves the efficiency of spectrum utilization and is viewed as a promising... Cognitive radio allows Secondary Users (SUs) to dynamically use the spectrum resource licensed to Prirmry Users (PUs), and significantly improves the efficiency of spectrum utilization and is viewed as a promising technology. In cognitive radio networks, the problem of power control is an important issue. In this paper, we mainly focus on the problem of power control for fading channels in cognitive radio networks. The spectrum sharing underlay scenario is considered, where SUs are allowed to coexist with PUs on the condition that the outage probability of PUs is below the maximum outage probability threshold limitation due to the interference caused by SUs. Moreover, besides the outage probability threshold which is defined to protect the performance of PUs, we also consider the maximum transmit power constraints for each SU. With such a setup, we emphasize the problem of power control to minimize the outage probability of each SU in fading channels. Then, based on the statistical information of the fading channel, the closed expression for outage probability is given in fading channels. The Dual-Iteration Power Control (DIPC) algorithm is also proposed to minimize the outage probability based on Perron-Frobenius theory and gradient descent method under the constraint condition. Finally, simulation results are illustrated to demonstrate the performance of the proposed scheme. 展开更多
关键词 cognitive radio power control outage probability Perron-Frobenius theory fading channel
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Stochastic Iterative Learning Control With Faded Signals 被引量:2
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作者 Ganggui Qu Dong Shen 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第5期1196-1208,共13页
Stochastic iterative learning control(ILC) is designed for solving the tracking problem of stochastic linear systems through fading channels. Consequently, the signals used in learning control algorithms are faded in ... Stochastic iterative learning control(ILC) is designed for solving the tracking problem of stochastic linear systems through fading channels. Consequently, the signals used in learning control algorithms are faded in the sense that a random variable is multiplied by the original signal. To achieve the tracking objective, a two-dimensional Kalman filtering method is used in this study to derive a learning gain matrix varying along both time and iteration axes. The learning gain matrix minimizes the trace of input error covariance. The asymptotic convergence of the generated input sequence to the desired input value is strictly proved in the mean-square sense. Both output and input fading are accounted for separately in turn, followed by a general formulation that both input and output fading coexists.Illustrative examples are provided to verify the effectiveness of the proposed schemes. 展开更多
关键词 FADING channels ITERATIVE learning control (ILC) KALMAN filtering mean-square convergence STOCHASTIC systems
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Routing Protocol Based on Grover’s Searching Algorithm for Mobile Ad-hoc Networks 被引量:3
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作者 孟利民 宋文波 《China Communications》 SCIE CSCD 2013年第3期145-156,共12页
In Mobile Ad-hoc Networks (MANETs), routing protocols directly affect various indices of network Quality of Service (QoS), so they play an important role in network performance. To address the drawbacks associated wit... In Mobile Ad-hoc Networks (MANETs), routing protocols directly affect various indices of network Quality of Service (QoS), so they play an important role in network performance. To address the drawbacks associated with traditional routing protocols in MANETs, such as poor anti-fading performance and slow convergence rate, for basic Dynamic Source Routing (DSR), we propose a new routing model based on Grover's searching algorithm. With this new routing model, each node maintains a node vector function, and all the nodes can obtain a node probability vector using Grover's algorithm, and then select an optimal routing according to node probability. Simulation results show that compared with DSR, this new routing protocol can effectively extend the network lifetime, as well as reduce the network delay and the number of routing hops. It can also significantly improve the anti-jamming capability of the network. 展开更多
关键词 Grover's channel fading additive bit error rate searching algorithm noise network delay
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Outage Probability Analysis of Relay Systems over K-μ Fading Channels 被引量:1
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作者 ZHANG Lingwen YANG Wenkao +1 位作者 ZHANG Jiayi LI Yongzhi 《China Communications》 SCIE CSCD 2014年第10期60-66,共7页
This paper provides an analytical framework for the outage probability evaluation of dual-hop decode-and-forward relay systems operating over K-μfading channels in the presence of co-channel interference. The interfe... This paper provides an analytical framework for the outage probability evaluation of dual-hop decode-and-forward relay systems operating over K-μfading channels in the presence of co-channel interference. The interferers are independent non-identically distributed K-μfading. An accurate analytical-form expression for the cumulative distribution function of the received signal power to interference and noise ratio is derived. Various numerical results are compared with Monte Carlo simulation results in order to corroborate the accuracy of the proposed expressions. Our results show that increasing the value of kappa of main links will decrease the outage probability of relay systems. Furthermore, the system performance degrades with the number of interferences. 展开更多
关键词 co-channel interference FADING performance analysis RELAY
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A new layered space-time detection algorithm for frequency selective fading multiple-input multiple-output channels based on particle filter 被引量:1
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作者 杜正聪 唐斌 刘立新 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第11期2481-2488,共8页
In this paper, a new observation equation of non-Gaussian frequency selective fading Bell Labs layered space time (BLAST) architecture system is proposed, which is used for frequency selective fading channels and no... In this paper, a new observation equation of non-Gaussian frequency selective fading Bell Labs layered space time (BLAST) architecture system is proposed, which is used for frequency selective fading channels and non-Gaussian noise in an application environment of BLAST system. With othogonal matrix triangularization (QR decomposition) of the channel matrix, the static observation equation of frequency selective fading BLAST system is transformed into a dynamic state space model, and then the particle filter is used for space-time layered detection. Making the full use of the finite alphabet of the digital modulation communication signal, the optimal proposal distribution can be chosen to produce particle and update the weight. Incorporated with current method of reducing error propagation, a new space-time layered detection algorithm is proposed. Simulation result shows the validity of the proposed algorithm. 展开更多
关键词 particle filter multiple-input multiple-output layered space-time structure frequency selective fading channels
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Aperture-averaged scintillation index and fade statistics in weak oceanic turbulence 被引量:1
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作者 Hao Wang Fu-Zeng Kang +2 位作者 Xuan Wang Wei Zhao Shu-Wei Sun 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第6期320-328,共9页
With the rapid demand for underwater optical communication(UOC), studies of UOC degradation by oceanic turbulence have attached increasing attention worldwide and become a research hot-spot in recent years. Previous s... With the rapid demand for underwater optical communication(UOC), studies of UOC degradation by oceanic turbulence have attached increasing attention worldwide and become a research hot-spot in recent years. Previous studies used a simplified and inaccurate oceanic turbulence spectrum, in which the eddy diffusivity ratio between temperature and salinity is assumed to be unity and the outer scale of turbulence is assumed to be infinite. However, both assumptions are not true in most of the actual marine environments. In this paper, based on the Rytov theory in weak turbulence, we derive analytical expressions of "the aperture-averaged scintillation index"(SI) for both plane and spherical waves, which can clearly demonstrate how SI is influenced by several key factors in UOC. Then, typical fade statistics of the UOC system in weak turbulence is discussed including the probability of fade, the expected number of fades per time, the mean fade time,signal-to-noise ratio and bit error rate. Our results show that spherical wave is preferable in the UOC system in weak turbulence compared to plane wave, and the aperture-averaged effect has a significant impact on UOC system's performance.Our results can be used to determine those key parameters for designing the UOC system over reasonable ranges. 展开更多
关键词 underwater optical communication(UOC) aperture-averaged scintillation index fade statistics
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FADE改进方法在医院治疗室冰箱药物管理中的应用 被引量:2
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作者 张翠华 王洪彬 熊淑英 《当代护士(中旬刊)》 2014年第7期179-180,共2页
目的规范医院治疗室冰箱药物的保存和使用,确保冰箱储存药物的安全。方法利用FADE持续质量改进法规范治疗室冰箱药物的管理与使用。结果通过FADE持续质量改进法使15个护理单元治疗室冰箱药物储存管理制度化、规范化、标准化,用药错误率... 目的规范医院治疗室冰箱药物的保存和使用,确保冰箱储存药物的安全。方法利用FADE持续质量改进法规范治疗室冰箱药物的管理与使用。结果通过FADE持续质量改进法使15个护理单元治疗室冰箱药物储存管理制度化、规范化、标准化,用药错误率为0。结论 FADE方法应用保证了治疗室冰箱药物的储存和使用安全,提高了护理管理的整体水平和护士满意度。 展开更多
关键词 fade方法 冰箱药物 管理
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Linearized Phase Detector Zero Crossing DPLL Performance Evaluation in Faded Mobile Channels 被引量:1
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作者 Qassim Nasir Saleh Al-Araji 《Circuits and Systems》 2011年第3期139-144,共6页
Zero Crossing Digital Phase Locked Loop with Arc Sine block (AS-ZCDPLL) is used to linearize the phase difference detection, and enhance the loop performance. The loop has faster acquisition, less steady state phase e... Zero Crossing Digital Phase Locked Loop with Arc Sine block (AS-ZCDPLL) is used to linearize the phase difference detection, and enhance the loop performance. The loop has faster acquisition, less steady state phase error, and wider locking range compared to the conventional ZCDPLL. This work presents a Zero Crossing Digital Phase Locked Loop with Arc Sine block (ZCDPLL-AS). The performance of the loop is analyzed under mobile faded channel conditions. The mobile channel is assumed to be two path fading channel corrupted by additive white Gaussian noise (AWGM). It is shown that for a constant filter gain, the frequency spread has no effect on the steady state phase error variance when the loop is subjected to a phase step. For a frequency step and under the same conditions, the effect on phase error is minimal. 展开更多
关键词 NON-UNIFORM Sampling Digital Phase Locked LOOPS ZERO CROSSING DPLL Mobile faded CHANNELS
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An Anti-Eavesdrop Transmission Scheduling Scheme Based on Maximizing Secrecy Outage Probability in Ad Hoc Networks 被引量:1
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作者 WANG Yajun LIAO Tongqing WANG Chuanan 《China Communications》 SCIE CSCD 2016年第1期176-184,共9页
In this paper,we consider a wireless ad hoc network consisting of multiple source nodes transmitting to their respective destinations,where an eavesdropper attempts to intercept their transmissions.We propose an optim... In this paper,we consider a wireless ad hoc network consisting of multiple source nodes transmitting to their respective destinations,where an eavesdropper attempts to intercept their transmissions.We propose an optimal transmission scheduling scheme to defend against the eavesdropper,where a source node having the highest secrecy rate is scheduled to access the wireless medium for transmitting to its destination in an opportunistic manner.To be specific,the secrecy rate between a pair of the source and destination in the presence of an eavesdropper varies temporally due to the wireless fading effect.The proposed optimal transmission scheduling scheme opportunistically selects a source node with the highest secrecy rate to transmit its data for the sake of maximizing the security of the ad hoc network against eavesdropping attacks.For comparison purposes,we also consider the conventional round-robin scheduling as a benchmark,where multiple source nodes take turns in accessing their shared wireless medium for transmitting to their respective destinations.We derive closed-form secrecy outage probability expressions of both the round-robin scheduling and the proposed optimal scheduling schemes over Rayleigh fading environments.Numerical results show that the proposed transmission scheduling scheme outperforms the conventional round-robin method in terms of its secrecy outage probability.Additionally,upon increasing the number of source-destination pairs,the secrecy outage probability of the round-robin scheme keeps unchanged,whereas the secrecy outage performance of the proposed transmission scheduling significantly improves,showing the security benefits of exploiting transmission scheduling for protecting wireless ad hoc networks against eavesdropping. 展开更多
关键词 transmission scheduling eavesdropping secrecy outage probability secrecy rate rayleigh fading
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Performance Analysis of Outage Probability and Error Rate of Square M-QAM in Mobile Wireless Communication Systems over Generalized α-μ Fading Channels with Non-Gaussian Noise
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作者 Fares S. Aimehmadi Osamah S. Badarneh 《China Communications》 SCIE CSCD 2018年第1期62-71,共10页
This paper derives new and exact closed-form expressions for the average symbol error rate(SER) of square M-ary quadrature amplitude modulation(M-QAM) in wireless communication systems over theα-μfading channels sub... This paper derives new and exact closed-form expressions for the average symbol error rate(SER) of square M-ary quadrature amplitude modulation(M-QAM) in wireless communication systems over theα-μfading channels subject to an additive non-Gaussian noise. The obtained expressions take into account static and mobile wireless receivers. In addition, a closed-form expression for the outage probability in mobile networks is obtained. Please note that all derived expressions in this paper a valid for integer and non-integer values of the fading parameters. Analytical results are presented to study the impact of noise shaping parameter, severity of fading, and mobility on the average SER. Monte-Carlo simulations results are also provided to validate the accuracy of the analytical results. 展开更多
关键词 α-μ FADING SYMBOL error rate NON-GAUSSIAN noise random WAYPOINT mobili-ty model
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Outage Probability Analysis for Modified Decode-and-Forward Model over Nakagami-m Fading Channels
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作者 啜钢 邹钰寒 刘振兴 《China Communications》 SCIE CSCD 2011年第3期145-153,共9页
This paper proposes a modified decodeand-forward(DAF) protocol with a three-node model,which contains two users and one destination.Each user can be either the source or the relay in different frames.We analyze the fo... This paper proposes a modified decodeand-forward(DAF) protocol with a three-node model,which contains two users and one destination.Each user can be either the source or the relay in different frames.We analyze the four cooperative cases in the first frame and run simulations to obtain the optimal power allocation coefficients in the second frame.The closed-form expression of outage probability is derived over Nakagami-m fading channels.Furthermore,we show that the proposed model has better performance than the non-cooperation system and traditional DAF strategy based on the derived outage probability. 展开更多
关键词 cooperative communication decodeand-forward Nakagami-m fading channel outage probability optimal power allocation
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Outage Analysis of Distributed Antenna Systems over Shadowed Nakagami-m Fading Channels
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作者 林思雨 钟章队 艾渤 《China Communications》 SCIE CSCD 2011年第2期103-110,共8页
This paper presents an outage analysis of distributed antennas system(DAS) suffering from shadowed Nakagami-m fading environment where the desired signal also suffers from co-channel interference. The desired signal a... This paper presents an outage analysis of distributed antennas system(DAS) suffering from shadowed Nakagami-m fading environment where the desired signal also suffers from co-channel interference. The desired signal and interfering signal are subjected to path loss,multipath and shadowing fading. Based on Wilkinson's method,the signal to interference ratio(SIR) probability density function(PDF) of fixed DAS is obtained. Some numerical results of outage probability with different parameters are analyzed. The analysis results can provide sufficient precision for evaluating the outage performance of DAS. 展开更多
关键词 distributed antennas system (DAS) outage probability nakagamim fading SHADOWING
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Outage performance of OFDM-based selective decode-and-forward cooperative networks over Weibull fading channels
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作者 Cai Chunxiao Yang Wendong Cai Yueming 《High Technology Letters》 EI CAS 2011年第3期285-289,共5页
The outage performance of OFDM-based decode-and-forward cooperative networks is studied. The channels are modeled as independent Weibull distributed coefficients. A closed-form expression for the outage probability is... The outage performance of OFDM-based decode-and-forward cooperative networks is studied. The channels are modeled as independent Weibull distributed coefficients. A closed-form expression for the outage probability is obtained for three selective relaying schemes in the Weibull fading channels and a derived optimum power allocation method based on the closed form expressions of outage probability debases the outage probability. Monte Carlo simulations verify the analytical results. 展开更多
关键词 OFDM cooperative communication Weibull fading channels DECODE-AND-FORWARD outage probability.
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Service Adaptable 3G Turbo Decoder for Indoor/Low Range Outdoor Environment
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作者 Costas CHAIKALIS Nicholas S. SAMARAS 《International Journal of Communications, Network and System Sciences》 2009年第8期704-713,共10页
For the well-known 3G mobile communications standard UMTS, four different service classes have been specified. Considering two turbo decoding algorithms, like SOVA and log-MAP, it would be desirable to use an efficien... For the well-known 3G mobile communications standard UMTS, four different service classes have been specified. Considering two turbo decoding algorithms, like SOVA and log-MAP, it would be desirable to use an efficient turbo decoder. In this paper this decoder is shown to adapt dynamically to different service scenarios, considering parameters like performance and complexity for indoor/low range outdoor operating en-vironment. The scenarios show that for streaming service class real-time class applications the proposed de-coding algorithm depends on data rate;for the majority of scenarios SOVA is proposed, whereas log-MAP is optimal for increased data rates and medium-sized frames. On the other hand, conversational service class real-time applications cannot be established. For the majority of non real-time applications (interactive and background service classes) either algorithm can be used, while log-MAP is proposed for medium data rates and frame lengths. 展开更多
关键词 Reconfigurable Systems Turbo DECODER UMTS Flat Reyleigh FADING Indoor/Low RANGE out-door Operating Environment
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Outage Performance of Opportunistic Amplify-and-Forward Relaying over Asymmetric Fading Environments
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作者 Sudhan Majhi Youssef Nasser Jean Francois Helard 《International Journal of Communications, Network and System Sciences》 2010年第5期430-433,共4页
This letter analyzes the outage probability of opportunistic amplify-and-forward relaying over asymmetric and independent but non-identically distributed (i.n.d) fading environments. The work investigates the scenario... This letter analyzes the outage probability of opportunistic amplify-and-forward relaying over asymmetric and independent but non-identically distributed (i.n.d) fading environments. The work investigates the scenarios where cooperative nodes are located at different geographical locations. As a result, the different signals are affected by different i.n.d fading channels, one may undergo Rician fading distribution and others may undergo Rayleigh fading distribution. In this letter, a lower bound of the outage probability for various asymmetric fading environments is derived at high SNR by applying the initial value theorem. The analytical model is validated through Monte-Carlo simulation results. 展开更多
关键词 outage Probability Opportunistic RELAYING AMPLIFY-AND-FORWARD RELAYING Rayleigh and RICIAN FADING CHANNELS ASYMMETRIC FADING CHANNELS Independent and Non-Identically Distributed
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Outage Performance of Cognitive Relay Networks with Best Relay Selection in Nakagami-m Channels
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作者 Zongsheng Zhang Qihui Wu +3 位作者 Jinlong Wang Xueqiang Zheng Xinhong Shao Cheng Tan 《Communications and Network》 2013年第3期166-170,共5页
This paper investigates the outage performance of a cognitive relay network considering best relay selection in Nakagami-m fading environment. The secondary user is allowed to use the spectrum when it meets the interf... This paper investigates the outage performance of a cognitive relay network considering best relay selection in Nakagami-m fading environment. The secondary user is allowed to use the spectrum when it meets the interference constraints predefined by primary user. Due to deep fading, cognitive source is unable to communicate directly with cognitive destination. As such, multiple relays are ready to deliver the signal from the cognitive source to cognitive destination. We select a single best relay and the selected relay uses decode-and-forward protocol. Specifically, we derive the exact outage probability expression, which provides an efficient means to evaluate the effects of several parameters. Finally, numerical simulation results are presented, which validate the correctness of the analytical analysis. 展开更多
关键词 COGNITIVE Realy NETWORKS (CRNs) Nakagami-m FADING outAGE PROBABILITY
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Estimation of Fading Statistics of Nakagami Channel with Weibull Distributed Tolerable Outage Time
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作者 Anjana Jain Prakash D. Vyavahare Leeladhar Arya 《Wireless Engineering and Technology》 2012年第2期77-82,共6页
Characterization of a mobile radio channel plays an important role in designing a reliable wireless communication system. Such channels are analyzed by two state model, namely satisfactory and outage state. This paper... Characterization of a mobile radio channel plays an important role in designing a reliable wireless communication system. Such channels are analyzed by two state model, namely satisfactory and outage state. This paper presents the analysis to estimate fading parameters of wireless channel with omission of certain outage durations which are considered as “Tolerance time”. Minimum outage duration which can be tolerated by a wireless fading channel to achieve desired packet error rate is defined as tolerance time. Normally a system with tolerable minimum outage time is analyzed based on Fade Duration Distribution (FDD) function over Rayleigh channel. In this paper Weibull function is used as FDD for varying tolerance time. The approach is simple and in general applicable from Rayleigh to Nakagami channels. The analysis is extended to study the effect of Tolerance time on channel fading statistics such as Average Fade Duration (AFD) and frequency of outage. Further the effects of various fade margin and Doppler spread on fading parameters are also investigated. The analysis can also be used in case of timeout expiration, connection resetting and congestion window control. 展开更多
关键词 Fading Statistics Tolerance TIME fade Duration Distribution FUNCTION Weibull FUNCTION NAKAGAMI Wireless CHANNEL Minimum outAGE TIME
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