- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Probabilistic forecasting of the clear-sky index using Markov-chain mixture distribution and copula models
摘要： Spectrum sensing is used to detect spectrum holes and find active primary users while randomly selecting channel for sensing lead to secondary user’s low throughput in high traffic cognitive radio networks. Spectrum prediction forecasts future channel states on the basis of historical information. A new frame structure is proposed in this letter for the imperfect spectrum prediction, resulting to select channels for sensing only from the channels predicted to be idle. Simulation results show that secondary user’s throughput is significantly enhanced by imperfect spectrum prediction. The impacts of traffic intensity, prediction errors, and channel number on the throughput are also investigated in this study.
关键词： frame structure,Imperfect spectrum prediction,cognitive radio networks
更新于2025-09-23 15:21:01
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[IEEE 2019 14th International Conference on Advanced Technologies, Systems and Services in Telecommunications (TELSIKS) - Nis, Serbia (2019.10.23-2019.10.25)] 2019 14th International Conference on Advanced Technologies, Systems and Services in Telecommunications (TELSIKS) - A Laser Beam for Boosting the Power Added Efficiency of an X-Band GaN MMIC Amplifier
摘要： Spectrum sensing is used to detect spectrum holes and find active primary users while randomly selecting channel for sensing lead to secondary user’s low throughput in high traffic cognitive radio networks. Spectrum prediction forecasts future channel states on the basis of historical information. A new frame structure is proposed in this letter for the imperfect spectrum prediction, resulting to select channels for sensing only from the channels predicted to be idle. Simulation results show that secondary user’s throughput is significantly enhanced by imperfect spectrum prediction. The impacts of traffic intensity, prediction errors, and channel number on the throughput are also investigated in this study.
关键词： frame structure,Imperfect spectrum prediction,cognitive radio networks
更新于2025-09-23 15:21:01
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Simultaneous Spectrum Sensing and Energy Harvesting
摘要： This paper proposes a new simultaneous spectrum sensing (SS) and energy harvesting (EH) scheme, called integrated SS-EH, where all of the incoming radio frequency (RF) power is used for EH. Then, SS is performed based on a fraction of the harvested power. The proposed approach does not require a separate energy detector which needs a power-hungry radio front end. Therefore, the energy consumption and hardware complexity for SS can be reduced significantly. Furthermore, it can increase the harvested energy over the conventional separated SS-EH scheme, where SS and EH are performed separately and thus only a fraction of incoming RF power can be used for EH. The combined benefit of reduced energy consumption for SS and increased energy harvest allows more energy to be available for communication, which results in an increase of the throughput. The probability of false alarm and missed detection, the average harvested energy, and the average throughput are analyzed in Rayleigh fading channel and compared with the conventional separated SS-EH scheme. Mixed SS and EH scheme is proposed in cooperative SS and EH environment where each sensor operates in either the integrated SS-EH or the separated SS-EH mode to improve the sensing accuracy at the fusion center.
关键词： mixed cooperative spectrum sensing,RF-powered cognitive radio networks,Integrated spectrum sensing and energy harvesting
更新于2025-09-23 15:21:01
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Suppression of Speckle Noise in Digital Holography With Spatial and Temporal Domain Depolarization
摘要： In this paper, we introduce transmit antenna selection/maximal-ratio combining (TAS/MRC) scheme in dual-hop randomize-and-forward (RaF) cognitive multiple-input multiple-output (MIMO) wiretap networks with outdated channel state information (CSI). In this network, the secondary transmitter adopts the TAS scheme to choose the antenna with the maximal received signal-to-noise ratio (SNR), while the secondary receiver and the eavesdropper adopt the MRC scheme to combine the received signals. To thoroughly assess the secrecy performance achieved by the TAS/MRC scheme and the impact of outdated CSI on the secrecy performance, we derive a new closed-form expression for the secrecy outage probability of dual-hop RaF cognitive MIMO wiretap networks. In order to achieve more insights on the application of TAS/MRC scheme, we further present tractable asymptotic secrecy outage probability at high SNR regimes under two distinct scenarios. From our analysis, several important concluding remarks are obtained as follows: 1) the RaF relaying strategy achieves better secrecy performance than that of the decode-and-forward relaying strategy for dual-hop cognitive MIMO wiretap networks; 2) outdated CSI decreases the secrecy diversity gain of the TAS/MRC scheme from NR min (NA, NB) to min (NR, NB); and 3) although TAS/MRC scheme cannot attain full secrecy diversity gain for the considered system with outdated CSI, it still can achieve an extra secrecy coding gain compared with the random antenna selection/MRC scheme.
关键词： Cognitive radio networks,secrecy outage probability,MIMO,outdated channel state information
更新于2025-09-19 17:13:59