Description: A Survey of Spectrum Sensing Algorithms The spectrum sensing problem has gained new aspects with cognitive radio and opportunistic spectrum access concepts. It is one of the most challenging issues in cognitive radio systems. In this paper, a survey of spectrum sensing methodologies for cognitive radio is presented. Various aspects of spectrum sensing problem are studied from a cognitive radio perspective and multi-dimensional spectrum sensing concept is introduced. Challenges associated with spectrum sensing are given and enabling spectrum sensing methods are reviewed. The paper explains the cooperative sensing concept and its various forms. External sensing algorithms and other alternative sensing methods are discussed. Furthermore, statistical modeling of network traffic and utilization of these models for prediction of primary user behavior is studied. Finally, sensing features of some current wireless standards are given. Platform: |
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Author:chenpeng3361 |
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Description: 认知无线电系统中多载波信号带外干扰的抑制，采用载波加权的方法降低认知无线电系统中认知用户信号对主用户信号的干扰
-Cognitive radio system in multi-carrier signal-band interference suppression, the use of carrier-weighted ways to reduce cognitive cognitive radio system users on the primary user signal signal interference Platform: |
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Author:antony |
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Description: Cognitive radio frequency spectrum detection-The spectrum sensing of a wideband frequency range is studied by dividing it into multiple subbands.
It is assumed that in each subband either a primary user (PU) is active or absent in a additive white Gaussian
noise environment with an unknown variance. It is also assumed that at least a minimum given number of
subbands are vacant of PUs. In this multiple interrelated hypothesis testing problem, the noise variance is
estimated and a generalised likelihood ratio detector is proposed to identify possible spectrum holes at a
secondary user (SU). Provided that it is known that a specific PU can occupy a subset of subbands
simultaneously, a grouping algorithm which allows faster spectrum sensing is proposed. The collaboration of
multiple SUs can also be considered in order to enhance the detection performance. The collaborative
algorithms are compared in terms of the required exchange information among SUs in some collaboration
methods. The simulation results show that the propos Platform: |
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Author:phillis |
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Description: adaptive spectrum sensing using SNAR comparioson and relative doppler shift (effect) between primary and secondary user Platform: |
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Author:hossein |
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Description: 认知无线电技术的提出是为提高频谱利用率，而认知无线实现的关键技术是频谱感知，众所周知协作检测提高了衰落环境中认知用户系统检测的性能，该文章是基于协作检测提出新的检测方案，利用了双门限方法提高了系统性能，兼顾带宽有限和增强性能两个方面，是基于门限检测的协作检测性能优化的前提。对以后门限优化协作检测非常有用。-In this paper, we employ a double threshold method in energy detector to perform spectrum sensing, while a fusion center in the cognitive radio network collects the local decisions and observational values of the secondary users, and then makes the final decision to determine whether the primary user is absence or not. Simulation results will show that the spectrum sensing performance channels is improved significantly under the proposed scheme as opposed to the conventional method. Platform: |
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Author:丽丽 |
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Description: 由于实际信道中的多径和阴影效应，单个认知用户频谱感知的性能受到影响，因此需要靠不同用户间的协同频谱感知来对抗多径和阴影效应。本设计要求在文中采用一种协作机制，即两用户进行协作频谱感知，提高主用户的检测率，减少检测时间，并且得到捷变增益。要求给出仿真结果。-As the actual channel of the multi-path and shadow effect, a single user of spectrum sensing of cognitive performance are affected, it needs to depend on collaboration between different users of spectrum sensing to combat multipath and shadow effects. The design requirements in the text using a cooperation mechanism, namely, two user collaborative spectrum sensing, to improve the detection rate of the primary users, reducing detection time, and get agility gain. Required to give simulation results. Platform: |
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Author:林熙怡 |
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Description: The spectrum sensing problem has gained new
aspects with cognitive radio and opportunistic spectrum access
concepts. It is one of the most challenging issues in cognitive
radio systems. In this paper, a survey of spectrum sensing
methodologies for cognitive radio is presented. Various aspects
of spectrum sensing problem are studied from a cognitive radio
perspective and multi-dimensional spectrum sensing concept is
introduced. Challenges associated with spectrum sensing are
given and enabling spectrum sensing methods are reviewed.
The paper explains the cooperative sensing concept and its
various forms. External sensing algorithms and other alternative
sensing methods are discussed. Furthermore, statistical modeling
of network traffic and utilization of these models for prediction
of primary user behavior is studied. Finally, sensing features of
some current wireless standards are given. Platform: |
Size: 456704 |
Author:Deepesh |
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Description: In this paper we uate the performance of cooperative spectrum sensing (CSS) where
each cognitive radio (CR) employs an improved energy detector (IED) with multiple antennas and
uses selection combining (SC) for detecting the primary user (PU) in noisy and faded sensing (S)
channels. We derive an expression for the probability of false alarm and expressions for probability
of missed detection in non-faded (AWGN) and Rayleigh faded sensing environments in terms of
cumulative distribution function (CDF). Each CR transmits its decision about PU via noisy and
faded reporting (R) channel to fusion center (FC).-In this paper we uate the performance of cooperative spectrum sensing (CSS) where
each cognitive radio (CR) employs an improved energy detector (IED) with multiple antennas and
uses selection combining (SC) for detecting the primary user (PU) in noisy and faded sensing (S)
channels. We derive an expression for the probability of false alarm and expressions for probability
of missed detection in non-faded (AWGN) and Rayleigh faded sensing environments in terms of
cumulative distribution function (CDF). Each CR transmits its decision about PU via noisy and
faded reporting (R) channel to fusion center (FC). Platform: |
Size: 720896 |
Author:suchita |
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Description: 频谱感知需要的认知无线电中顺序，寻找机会频谱的灵活使用。此外，它是干扰的管理造成水平的关键向初级用户 （PUs） 的频谱。遥感提供了
无线电操作环境的意识。认知电台可然后适应它的参数如载波频率电源和波形动态调整提供最好的服务可用的连接，以满足用户的需求范围内
对干扰约束。无线通信系统中，我们通常有一些对波形的知识和结构或统计属性的信号的频谱的主要用户使用。这种知识可能相关的调制
计划、 符号或芯片的信号，通道的速率。(Spectrum sensing requires the order of cognitive radio, looking for flexible use of opportunistic spectrum. In addition, it is the spectrum that disturbs the level of management caused by primary users (PUs). Remote sensing provides awareness of the radio operating environment. Cognitive stations can then adapt to its parameters such as carrier frequency power and waveform dynamics to provide the best service available to connect to meet user constraints on interference requirements. In wireless communication systems, we usually have some primary users who have knowledge of the waveform and the spectrum of the signal of the structure or statistic properties. This knowledge may be related to the modulation scheme, symbol or chip signal, channel speed.) Platform: |
Size: 12288 |
Author:晓骸 |
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Search - primary user in spectrum sensing