- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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[IEEE 2018 New Trends in Signal Processing (NTSP) - Liptovsky Mikulá?, Slovakia (2018.10.10-2018.10.12)] 2018 New Trends in Signal Processing (NTSP) - Possibilities of Using FSO/RF Technology in Military Communication Systems
摘要： The article presents an overview of selected aspects of wireless communications considering military applications. The main attention is paid to performance analysis of radio and free space optics technologies. There are also presented some activities to get new capabilities of wireless communications using procedure of dynamic spectrum access, wideband and narrowband radio system, and free space optical system operated in infrared spectrum. In the summary, possibilities of radio-optical hybrid communication systems and their application in military areas have been defined.
关键词： hybrid wireless communications,frequency management,software-defined radio,frequency broker,cognitive radio
更新于2025-09-23 15:22:29
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Optically reconfigurable planar monopole antenna for cognitive radio application
摘要： Frequency reconfigurable antenna is one of the important elements needed for cognitive radio application. Such antenna can be designed using highly resistive (HR) silicon (Si) operating as an optical switch. This letter presents a novel frequency reconfigurable planar monopole antenna suitable for cognitive radio application. The antenna is designed using HR Si working as an optical switch. The main idea behind the design of antenna is the redistribution of surface current on the antenna while changing the state of Si switches optically from high resistance to low resistance. The antenna is highly compact and uses only two switches for multiband reconfiguration. It is switchable on 1.9 GHz, 2.75 GHz, 3.7 GHz, 4.1 GHz, 4.6 GHz, 4.8 GHz, and 7.6 to 11 GHz frequency bands. Simulated and measured results are presented for the antenna. To the best of authors knowledge, this is the first multiband optically reconfigurable planar monopole antenna.
关键词： high-resistive (HR) silicon,optical excitation,low-resistive (LR) silicon,planar monopole antenna,cognitive radio,reconfigurable,multiband
更新于2025-09-23 15:22:29
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High sensitivity simple structured displacement sensor using corrugated substrate-integrated waveguide (CSIW)
摘要： Cognitive radio is a promising technology for sharing the underutilized frequency bands that have been licensed to primary users. However, due to the uncertainty in detecting the existence of the primary user, the secondary user may interfere with the primary users when both primary and secondary users are active simultaneously. Therefore, understanding the interference and its consequences on the cognitive network is critical. Unlike the statistical models previously reported in the literature that aim at approximation of the interference, based on the solid mathematical analysis, we propose an accurate model for describing the co-channel interference with probability density function, cumulative distribution function, mean, and variance of the interference suffered by the primary users. The proposed model not only takes into account a number of factors, such as the spectrum-sensing scheme, the spatial distribution of secondary users, and the channel conditions, including shadowing and Nakagami fading, but also gives an exact mathematical expression of the influences from these factors. The developed framework supports practical applications such as evaluating the cognitive network of any spatial shape and density of the secondary users and the methods of power control and spectrum sensing used by the secondary users. Simulation results are provided to verify the effectiveness of the analytical model.
关键词： cognitive radio,Interference modeling,cognitive network
更新于2025-09-23 15:21:01
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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 2018 IEEE 8th International Conference Nanomaterials: Application & Properties (NAP) - Zatoka, Ukraine (2018.9.9-2018.9.14)] 2018 IEEE 8th International Conference Nanomaterials: Application & Properties (NAP) - Optical and Thermal Analysis of PVB Encapsulant Polymer Functionalized with Luminescent Organic Dye as Emerging Material for Photovoltaic Application
摘要： Wireless sensor networks (WSNs) can utilize the unlicensed industrial, scienti?c, and medical (ISM) band to communicate the sensed data. The ISM band has been already saturated due to the overlaid deployment of WSNs. To solve this problem, WSNs have been powered up by cognitive radio (CR) capability. By using CR capability, WSNs can utilize the spectrum holes opportunistically. The sensor nodes, which need large bandwidth to transmit their sensed data from source to destination require some scheme, which should be able to provide them a wide band channel whenever required. Channel bonding (CB) is a technique through which multiple contiguous channels can be combined to form a single wide band channel. By using CB technique, CR-based WSN nodes attempt to ?nd and combine contiguous channels to avail larger bandwidth. In this paper, we show that by increasing the number of channels, the probability of ?nding contiguous channels decreases. Moreover, we then propose a primary-radio (PR) user-activity-aware CB algorithm and compare it with three state-of-the-art schemes: SWA, KNOWS, and AGILE. It has been demonstrated through extensive NS-2 simulations that intelligent CB decisions can reduce harmful interference to PR nodes. We ?nd that CB in CR sensor networks attempts to provide greater bandwidth and utilizes the spectrum effectively.
关键词： cognitive radio,dynamic spectrum access,wireless sensor networks,Channel bonding
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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[IEEE 2019 IEEE 21st Electronics Packaging Technology Conference (EPTC) - Singapore, Singapore (2019.12.4-2019.12.6)] 2019 IEEE 21st Electronics Packaging Technology Conference (EPTC) - An LTCC Based H-Antenna Aperture Coupled to an On-Chip Antenna for 2.4 GHz Long Range Transmitters
摘要： The latest trends in spectrum trading allow secondary users (SUs) to employ hybrid access models and exploit bandwidth employing either opportunistic spectrum access or exclusive spectrum access of vacant frequency bands (FBs) leased for exclusive usage. In this paper, the spectrum trading problem is addressed in an operational framework, where a primary spectrum owner (PSO) allocates specific FBs to a number of primary users (PUs) and at the same time allows SUs belonging to multiple service classes to operate opportunistically in a part of the spectrum primarily allocated to the PU operation. By offering exclusive bandwidth-price contracts to SUs in FBs, which are excluded from the PU access, the PSO expects additional revenue. In this framework, the PSO aims at maximizing its revenue through optimal contract design that considers the multiple SU service classes, about which the PSO may have at its disposal either complete or incomplete information. In the first case, it is proven that only one type of contract destined for the highest SU service class is profitable to the PSO. In the second case, two heuristic algorithms are proposed for the optimal contract design corresponding to offering a single contract or multiple contracts to various service classes. The simulation results for the complete and incomplete information cases have been examined with regard to the SU service classes and the number and transmission specifications of the PUs. The two proposed algorithms manage to address the incomplete information case and be close to the optimal values obtained when complete information is available. Finally, the social welfare, as the aggregate expected utility of all parties involved, is examined.
关键词： spectrum trading,cognitive radio,Dynamic spectrum access,contract theory,hybrid spectrum access
更新于2025-09-23 15:21:01
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Broadband Cognitive Radio Enabled by Photonics
摘要： Cognitive radio is considered as a possible disruptive force to improve the spectral resource efficiency through sensing and interacting with the environment. Traditional electrical technologies to implement the cognitive radio face challenges in terms of bandwidth, resolution, and speed. In this paper, the concept and architecture of broadband cognitive radio systems enabled by photonics are proposed. Key microwave photonic techniques for the architecture are reviewed, including the photonics-based spectrum sensing, the photonic arbitrary waveform generation, the photonics-based self-interference cancellation processing, and the microwave photonic dechirp processing and radar imaging. A preliminary demonstration of a cognitive radar system enabled by photonics is performed. The future possible research directions on this topic are discussed.
关键词： Cognitive radio,spectrum sensing,microwave photonics,radar imaging,self-interference cancellation,waveform generation
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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[IEEE 2019 IEEE Innovative Smart Grid Technologies - Asia (ISGT Asia) - Chengdu, China (2019.5.21-2019.5.24)] 2019 IEEE Innovative Smart Grid Technologies - Asia (ISGT Asia) - Research on Estimation of Regional Distributed Photovoltaic Output Based on K-medoids Algorithm
摘要： The analysis presented in this paper indicates that the FM radio spectrum is underutilized in the areas of the continental United States that have a population of 100 000 or less. These locations have vacant FM radio spectrum of at least 13 MHz with suf?cient spectrum spacing between adjacent FM radio channels. The spectrum spacing provides the required bandwidth for data transmission and provides enough bandwidth to minimize interference introduced by neighboring predicted and unpredicted FM radio stations and other low-power short-range Internet of Thing (IoT) devices. To ensure that low-power short-range IoT devices maintain reliable communications vacant radio spectrum, such as the FM radio spectrum in these areas, will need to be used through cognitive radio.
关键词： cognitive radio,Internet of things,FM radio
更新于2025-09-23 15:19:57