As we know, the future generation com-munication system is on the way to bedigitalized, integrated, broadband, intel-ligent, standardized and customized, andthe personal wireless communication systemmeets the demands....As we know, the future generation com-munication system is on the way to bedigitalized, integrated, broadband, intel-ligent, standardized and customized, andthe personal wireless communication systemmeets the demands.ZTE’s personal wireless communicationsystem (ZXPCS) is based on the personalhandset system (PHS) and deployed in morethan 110 cities in China. It is working well andwidely accepted by the carriers, which makesgreat contributions to the local economy and展开更多
This article describes a new miniaturized omni-directional antenna with quasi-self-complementary structure for wireless communication applications. A novel ground structure composed of five rectangular plates is propo...This article describes a new miniaturized omni-directional antenna with quasi-self-complementary structure for wireless communication applications. A novel ground structure composed of five rectangular plates is proposed to enhance the impedance bandwidth and reduce the antenna size. The proposed antenna is comprised of two patches surrounded by the ground structure. Two metal patches of the antenna are located on two opposite sides of the dielectric substrate. The feed patch is used to excite the radiation patch. This unique design is realized by properly choosing the suitable feed patch shape, selecting similar slot shape on the radiation patch, and tuning their dimensions. The proposed antenna with an extremely small size of 6 mm × 9 mm has an operating impedance bandwidth ranging from 4.5 to 6.1 GHz for S<sub>11</sub> < -10 dB, which also covers the two IEEE 802.11a wireless local area network bands (5.15 - 5.35 GHz and 5.725 - 5.825 GHz). In addition to be very small in size, the antenna exhibits omni-directional radiation patterns in the entire operating bandwidth and low cross polarization. The distortionless time domain performance of the antenna is confirmed by investigation of the phase response and group delay. The obtained results in both frequency and time domain show that the proposed antenna is suitable for use in wireless communication systems.展开更多
This work presents a new bendable antenna for worldwide interoperability for microwave access (WiMAX) wireless communication systems. These antennas, transparent and flexible, will be easily integrated into various md...This work presents a new bendable antenna for worldwide interoperability for microwave access (WiMAX) wireless communication systems. These antennas, transparent and flexible, will be easily integrated into various mdia and in particular OLED lighting which could be part of the public lighting network of tomorrow as well as on all display media. The integration of these antennas as close as possible to the end-user is a possible solution to reduce the energy consumption which goes hand in hand with the increase in the data rate. This kind of new antenna, designed to be integrated in organic light-emitting diode (OLED), was modeled from a transparent VeilShieldTM conductive fabric and was placed on a 100% polyester substrate with a thickness of 1.5 mm and a loss tangent of 0.02. We have tested and evaluated the characteristic parameters of our antenna, namely the reflection coefficient, the radiation pattern and the gain, to find out the performance of our proposed design. The performance of the transparent conductive fabric integrated in the 100% polyester substrate is tested for the application of flexible antenna operating at 3.5 GHz with a gain value of 5.38 dB. We have integrated this proposed new antenna with the OLED light source containing four layers of different materials and electrical properties: aluminum cathode layer, polymer layer, indium tin oxide (ITO) anode layer and glass substrate layer. After integration, the resonant frequency shifted to 3.52 GHz with a gain value of 4.61 dB. In addition, we also tested the concave bending on the reflection coefficient of the proposed flexible antenna taking into account the different bending angles. This work demonstrates the possibility of integrating these unconventional materials used for the proposed antenna within the OLED despite weak effects on the resonant frequency and the gain of the proposed antenna after integration.展开更多
In the intensity modulation and direct detection (IM/DD) multiple-input multiple-output (MIMO) optical wireless communication systems, a direct-current-biased adaptive modulation scheme is proposed to guarantee th...In the intensity modulation and direct detection (IM/DD) multiple-input multiple-output (MIMO) optical wireless communication systems, a direct-current-biased adaptive modulation scheme is proposed to guarantee the nonnegative property of transmitted signals, and the MIMO channel is converted to a parallel channel by using a singular value decomposition. Besides, a QR decomposition and successive interference cancellation based adaptive modulation scheme is proposed, and the MIMO channel can be simplified to a parallel channel under the bit error ratio (BER) target constraint. The power is optimally allocated to each sub-channel to maximize the data rate. Simulation results show that the proposed adaptive modulation schemes can effectively improve the transmission rate of the systems under the BER target and constant optical power constraints. The proposed adaptive modulation schemes make use of the multiplexing gain of the MIMO techniques, and can further improve the spectrum efficiency of optical wireless systems.展开更多
The fifth generation (5G) wireless communication is currently a hot research topic and wireless communication systems on high speed railways (HSR) are important applications of 5G technologies. Existing stud- ies ...The fifth generation (5G) wireless communication is currently a hot research topic and wireless communication systems on high speed railways (HSR) are important applications of 5G technologies. Existing stud- ies about 5G wireless systems on high speed railways (HSR) often utilize ideal channel parameters and are usually based on simple scenarios. In this paper, we evaluate the down- link throughput of 5G HSR communication systems on three typical scenarios including urban, cutting and viaduct with three different channel estimators. The channel parameters of each scenario are generated with tapped delay line (TDL) models through ray-tracing sim- ulations, which can be considered as a good match to practical situations. The channel estimators including least square (LS), linear minimum mean square error (LMMSE), and our proposed historical information based ba- sis expansion model (HiBEM). We analyze the performance of the HiBEM estimator in terms of mean square error (MSE) and evaluate the system throughputs with different channel estimates over each scenario. Simulation results are then provided to corroborate our proposed studies. It is shown that our HiBEM estimator outperforms other estimators and that the sys-tem throughput can reach the highest point in the viaduct scenario.展开更多
To reduce the network deployment cost and provide voice, message and low rate data services in remote pastoral areas of Tibet effectively, an integrated wireless communication system utilizing MANET(Mobile Ad hoc Netw...To reduce the network deployment cost and provide voice, message and low rate data services in remote pastoral areas of Tibet effectively, an integrated wireless communication system utilizing MANET(Mobile Ad hoc Network) is proposed. The sparse mobile devices, assisted with the solar-powered multi-functional standing stations mainly on networking maintenance and routing arrangement, self-organize into a MANET. The topology of the standing stations is designed for networking robust and to simplify the routing method and energy strategy. Then in the OMNe T++(Objective Modular Network Test bed in C++) simulation, the energy consumption is analysis while adjusting routing with the different energy status of the standing stations. The result shows that the standing stations should adjust routing as well as control the mobile devices' activity level according to the energy states of the standing stations and their adjacent mobile devices.展开更多
The Optical Wireless Communication(OWC)offers the high capacity of optical fiber communication with the flexibility of wireless communication.Since it works in the optical region of the ElectroMagnetic(EM)spectrum,it ...The Optical Wireless Communication(OWC)offers the high capacity of optical fiber communication with the flexibility of wireless communication.Since it works in the optical region of the ElectroMagnetic(EM)spectrum,it guarantees safety and security which are critical in radio and microwave frequency communication.The principal objective of this paper is to analyze the indoor OWC systems on these guaranteed features,and safety and security are jointly denoted by the term green.The high obstacle impermeability of optical signals and their directivity strengthen the security of indoor OWC data transmission.The confidentiality and authenticity of optical wireless data can also be preserved with the Quantum Key Distribution(QKD).This paper provides a technological overview and a review of literature about the OWC system that helps to identify the challenges in the path of a ubiquitous deployment of green wireless communication systems.Significant advancements in the sources and detectors are discussed together with the coding,modulation and multiplexing techniques for making highly robust OWC links.The ubiquitous deployment of green OWC necessitates the development of optical transmitters and receivers,performance enhancement techniques,incorporation of uplink and energy harvesting abilities,and safety and security enhancement techniques.Hence,a special emphasis is placed on these aspects and their challenges towards the green implementation.Furthermore,the paper explores some significant indoor applications based on the OWC that have great impacts on the Next Generation Networks(NGN)and the Internet of Things(IoT).展开更多
With the rapid development of wireless communications systems, different system standards are being merged. Operators take stringent measures to reduce Operational Expenditure (OPEX) and Capital Expenditure (CAPEX...With the rapid development of wireless communications systems, different system standards are being merged. Operators take stringent measures to reduce Operational Expenditure (OPEX) and Capital Expenditure (CAPEX); and as a result, soft base stations supporting multiple standards become the evolutionary tend of wireless base stations. This paper introduces the background of soft base stations and analyzes their architecture design, system modules. The key technologies in system implementation and future directions are also presented.展开更多
This paper investigates the jammerassisted multi-channel covert wireless communication(CWC)by exploiting the randomness of sub-channel selection to confuse the warden.In particular,we propose two sub-channel selection...This paper investigates the jammerassisted multi-channel covert wireless communication(CWC)by exploiting the randomness of sub-channel selection to confuse the warden.In particular,we propose two sub-channel selection transmission schemes,named random sub-channel selection(RSS)scheme and maximum sub-channel selection(MSS)scheme,to enhance communication covertness.For each proposed scheme,we first derive closed-form expressions of the transmission outage probability(TOP),the average effective rate,and the minimum average detection error probability(DEP).Then,the average effective covert rate(ECR)is maximized by jointly optimizing the transmit power at the transmitter and the number of sub-channels.Numerical results show that there is an optimal value of the number of sub-channels that maximizes the average ECR.We also find that to achieve the maximum average ECR,a larger number of subchannels are needed facing a stricter covertness constraint.展开更多
Massive multiple-input multiple-output(MIMO) requires a large number(tens or hundreds) of base station antennas serving for much smaller number of terminals, with large gains in energy efficiency and spectral effi...Massive multiple-input multiple-output(MIMO) requires a large number(tens or hundreds) of base station antennas serving for much smaller number of terminals, with large gains in energy efficiency and spectral efficiency compared with traditional MIMO technology. Large scale antennas mean large scale radio frequency(RF) chains. Considering the plenty of power consumption and high cost of RF chains, antenna selection is necessary for Massive MIMO wireless communication systems in both transmitting end and receiving end. An energy efficient antenna selection algorithm based on convex optimization was proposed for Massive MIMO wireless communication systems. On the condition that the channel capacity of the cell is larger than a certain threshold, the number of transmit antenna, the subset of transmit antenna and servable mobile terminals(MTs) were jointly optimized to maximize energy efficiency. The joint optimization problem was proved in detail. The proposed algorithm is verified by analysis and numerical simulations. Good performance gain of energy efficiency is obtained comparing with no antenna selection.展开更多
The concept of virtualization of wireless communication systems is based on the open and scalable hardware platform of software radios in the personal communication network. The base station is divided into four compo...The concept of virtualization of wireless communication systems is based on the open and scalable hardware platform of software radios in the personal communication network. The base station is divided into four components according to their functions: antenna, IF, baseband, and control, which are connected by the ATM network. Virtualization provides great benefits such as fast handoff and easy realization of different macrodiversity algorithms. Macrodiversity can not be easily realized in conventional cellular systems. An exact analysis is presented for the performance of maximal ratio combining (MRC) macrodiversity in virtualized wireless communication systems. The results show that compared with soft handoff in CDMA systems, MRC can greatly increase the reverse link capacity.展开更多
This paper focuses on the design and implementation of an active multibeam antenna system for massive MIMO applications in 5G wireless communications.The highly integrated active multibeam antenna system is designed a...This paper focuses on the design and implementation of an active multibeam antenna system for massive MIMO applications in 5G wireless communications.The highly integrated active multibeam antenna system is designed and implemented at 5.8 GHz with 64 RF Channels and 256 antenna elements.The 64-channel highly integrated active multibeam antenna system provides a verification platform for digital beamforming algorithm and massive MIMO channel estimation for next generation wireless communications.展开更多
This study explores the application of single photon detection(SPD)technology in underwater wireless optical communication(UWOC)and analyzes the influence of different modulation modes and error correction coding type...This study explores the application of single photon detection(SPD)technology in underwater wireless optical communication(UWOC)and analyzes the influence of different modulation modes and error correction coding types on communication performance.The study investigates the impact of on-off keying(OOK)and 2-pulse-position modulation(2-PPM)on the bit error rate(BER)in single-channel intensity and polarization multiplexing.Furthermore,it compares the error correction performance of low-density parity check(LDPC)and Reed-Solomon(RS)codes across different error correction coding types.The effects of unscattered photon ratio and depolarization ratio on BER are also verified.Finally,a UWOC system based on SPD is constructed,achieving 14.58 Mbps with polarization OOK multiplexing modulation and 4.37 Mbps with polarization 2-PPM multiplexing modulation using LDPC code error correction.展开更多
Traditional magnetically coupled resonant wireless power transfer technology uses fixed distances between coils for research,to prevent fluctuations in the receiving voltage,and lead to reduce transmission efficiency....Traditional magnetically coupled resonant wireless power transfer technology uses fixed distances between coils for research,to prevent fluctuations in the receiving voltage,and lead to reduce transmission efficiency.This paper proposes a closed-loop control wireless communication wireless power transfer system with a wearable four-coil structure to stabilize the receiving voltage fluctuation caused by changes in the displacement between the coils.Test results show that the system can provide stable receiving voltage,no matter how the distance between the transmitting coil and the receiving coil is changed.When the transmission distance is 20 mm,the power transfer efficiency of the system can reach 18.5%under the open-loop state,and the stimulus parameters such as the stimulation period and pulse width can be adjusted in real time through the personal computer terminal.展开更多
This paper presents a wide-bandwidth back-illuminated modified uni-traveling-carrier photodiode(MUTC-PD)packaged with standard WR-5 rectangular waveguide for high-speed wireless communications.With optimized epitaxy s...This paper presents a wide-bandwidth back-illuminated modified uni-traveling-carrier photodiode(MUTC-PD)packaged with standard WR-5 rectangular waveguide for high-speed wireless communications.With optimized epitaxy structure and coplanar waveguide electrodes,the fabricated 4-μm-diameter PD exhibits ultra-flat frequency response and high saturation power.Integrated passive circuits including low-loss bias-tee and E-plane probe are designed to package the PD into a compact module with waveguide output.The packaged PD module has demonstrated a flat frequency response with fluctuations within±2.75 d B over a broadband of 140–220 GHz and a high saturated output power of-7.8 d Bm(166μW)at 140 GHz.For wireless communication applications,the packaged PD is used to implement 1-m free space transmission at carrier frequencies of 150.5 and 210.5 GHz,with transmission rates of 75 and 90 Gbps,respectively.展开更多
In this study,a real-time rotor temperature monitoring system for large turbogenerators using SmartMesh IP wireless network communication technology was designed and tested.The system is capable of providing comprehen...In this study,a real-time rotor temperature monitoring system for large turbogenerators using SmartMesh IP wireless network communication technology was designed and tested.The system is capable of providing comprehensive,accurate,continuous,and reliable real-time temperature monitoring for turbogenerators.Additionally,it has demonstrated satisfactory results in a real-time monitoring test of the rotor temperature of various famous large-scale turbogenerators and giant nuclear power half-speed turbogenerators designed and manufactured in China.The development and application of this wireless temperature measurement system would aid in improving the intelligent operation quality,safety,and stability of China’s large turbine generators and even the entire power system.展开更多
As the competition for marine resources is increasingly fierce,the security of underwater acoustic communication has attracted a great deal of attention.The information and location of the communicating platform can b...As the competition for marine resources is increasingly fierce,the security of underwater acoustic communication has attracted a great deal of attention.The information and location of the communicating platform can be leaked during the traditional underwater acoustic communication technology.According to the unique advantages of chaos communication,we put forward a novel communication scheme using complex parameter modulation and the complex Lorenz system.Firstly,we design a feedback controller and parameter update laws in a complex-variable form with rigorous mathematical proofs(while many previous references on the real-variable form were only special cases in which the imaginary part was zero),which can be realized in practical engineering;then we design a new communication scheme employing parameter modulation.The main parameter spaces of the complex Lorenz system are discussed,then they are adopted in our communication scheme.We also find that there exist parametric attractors in the complex Lorenz system.We make numerical simulations in two channels for digital signals and the simulations verify our conclusions.展开更多
An important problem in wireless communication networks (WCNs) is that they have a minimum number of resources, which leads to high-security threats. An approach to find and detect the attacks is the intrusion detecti...An important problem in wireless communication networks (WCNs) is that they have a minimum number of resources, which leads to high-security threats. An approach to find and detect the attacks is the intrusion detection system (IDS). In this paper, the fuzzy lion Bayes system (FLBS) is proposed for intrusion detection mechanism. Initially, the data set is grouped into a number of clusters by the fuzzy clustering algorithm. Here, the Naive Bayes classifier is integrated with the lion optimization algorithm and the new lion naive Bayes (LNB) is created for optimally generating the probability measures. Then, the LNB model is applied to each data group, and the aggregated data is generated. After generating the aggregated data, the LNB model is applied to the aggregated data, and the abnormal nodes are identified based on the posterior probability function. The performance of the proposed FLBS system is evaluated using the KDD Cup 99 data and the comparative analysis is performed by the existing methods for the evaluation metrics accuracy and false acceptance rate (FAR). From the experimental results, it can be shown that the proposed system has the maximum performance, which shows the effectiveness of the proposed system in the intrusion detection.展开更多
The internet of the underground things(IoUT)is an emerging field that concerns connected underground sensing nodes and can find applications in various fields such as geotechnical engineering,precision agriculture,and...The internet of the underground things(IoUT)is an emerging field that concerns connected underground sensing nodes and can find applications in various fields such as geotechnical engineering,precision agriculture,and search and rescue operations.The complex underground environment and multiphase nature of the soil pose challenges to wireless underground communication.Most existing studies on wireless underground communication focus on the use of electromagnetic waves.However,as a highly lossy material for electromagnetic waves,soil can limit the range and reliability of data transmission.Inspired by subterranean animals that rely on vibrations or seismic waves for underground communication,the prototype system developed in this study is based on vibration.This system includes a bioinspired vibrating source,a micro-electromechanical system(MEMS)accelerometer,a microcontroller,and a set of algorithms for encoding and decoding information.Specifically,the mole ratsinspired source is small in size,low in cost,and energy-efficient.An on-off-keying decoding algorithm enhanced with an error-correction algorithm is found to be robust in transmitting textual and imaginary information.With the current design,a maximum transmission bit rate of 16e17 bits per second and a transmission distance of 80 cm can be achieved.The bit error ratio is as low as 0.1%,demonstrating the robustness of the algorithms.The performance of the developed system shows that seismic waves produced by vibration can be used as an information carrier and can potentially be implemented in the IoUT.展开更多
Aerostat platforms could serve as potential aerial platforms because of their low cost,long flight times,and easy load recovery.They are suitable for emergency communication,early warnings,Earth observations,and other...Aerostat platforms could serve as potential aerial platforms because of their low cost,long flight times,and easy load recovery.They are suitable for emergency communication,early warnings,Earth observations,and other fields.The air-ground communication link between an aerostat platform and the ground is the basic guarantee for aerostat measurement control and service transmission.In traditional aerostat applications,platform measurement control and service transmission usually use different links.The load and ground equipment are complex,and the energy,load,and size of the platform are greatly occupied.In this paper,we propose a Beidou-assisted air-ground communication ground for a near-space platform that uses Beidou's positioning and communication functions to provide tracking and guidance information for the ground station.An air-ground wireless communication mode integrating measurement control and service transmission is achieved.The flight test shows that the system can effectively meet the practical application requirements.展开更多
文摘As we know, the future generation com-munication system is on the way to bedigitalized, integrated, broadband, intel-ligent, standardized and customized, andthe personal wireless communication systemmeets the demands.ZTE’s personal wireless communicationsystem (ZXPCS) is based on the personalhandset system (PHS) and deployed in morethan 110 cities in China. It is working well andwidely accepted by the carriers, which makesgreat contributions to the local economy and
文摘This article describes a new miniaturized omni-directional antenna with quasi-self-complementary structure for wireless communication applications. A novel ground structure composed of five rectangular plates is proposed to enhance the impedance bandwidth and reduce the antenna size. The proposed antenna is comprised of two patches surrounded by the ground structure. Two metal patches of the antenna are located on two opposite sides of the dielectric substrate. The feed patch is used to excite the radiation patch. This unique design is realized by properly choosing the suitable feed patch shape, selecting similar slot shape on the radiation patch, and tuning their dimensions. The proposed antenna with an extremely small size of 6 mm × 9 mm has an operating impedance bandwidth ranging from 4.5 to 6.1 GHz for S<sub>11</sub> < -10 dB, which also covers the two IEEE 802.11a wireless local area network bands (5.15 - 5.35 GHz and 5.725 - 5.825 GHz). In addition to be very small in size, the antenna exhibits omni-directional radiation patterns in the entire operating bandwidth and low cross polarization. The distortionless time domain performance of the antenna is confirmed by investigation of the phase response and group delay. The obtained results in both frequency and time domain show that the proposed antenna is suitable for use in wireless communication systems.
文摘This work presents a new bendable antenna for worldwide interoperability for microwave access (WiMAX) wireless communication systems. These antennas, transparent and flexible, will be easily integrated into various mdia and in particular OLED lighting which could be part of the public lighting network of tomorrow as well as on all display media. The integration of these antennas as close as possible to the end-user is a possible solution to reduce the energy consumption which goes hand in hand with the increase in the data rate. This kind of new antenna, designed to be integrated in organic light-emitting diode (OLED), was modeled from a transparent VeilShieldTM conductive fabric and was placed on a 100% polyester substrate with a thickness of 1.5 mm and a loss tangent of 0.02. We have tested and evaluated the characteristic parameters of our antenna, namely the reflection coefficient, the radiation pattern and the gain, to find out the performance of our proposed design. The performance of the transparent conductive fabric integrated in the 100% polyester substrate is tested for the application of flexible antenna operating at 3.5 GHz with a gain value of 5.38 dB. We have integrated this proposed new antenna with the OLED light source containing four layers of different materials and electrical properties: aluminum cathode layer, polymer layer, indium tin oxide (ITO) anode layer and glass substrate layer. After integration, the resonant frequency shifted to 3.52 GHz with a gain value of 4.61 dB. In addition, we also tested the concave bending on the reflection coefficient of the proposed flexible antenna taking into account the different bending angles. This work demonstrates the possibility of integrating these unconventional materials used for the proposed antenna within the OLED despite weak effects on the resonant frequency and the gain of the proposed antenna after integration.
基金The National High Technology Research and Development Program of China(863 Program)(No.2013AA013601)the National Science and Technology M ajor Project of China(No.2015ZX03004009)
文摘In the intensity modulation and direct detection (IM/DD) multiple-input multiple-output (MIMO) optical wireless communication systems, a direct-current-biased adaptive modulation scheme is proposed to guarantee the nonnegative property of transmitted signals, and the MIMO channel is converted to a parallel channel by using a singular value decomposition. Besides, a QR decomposition and successive interference cancellation based adaptive modulation scheme is proposed, and the MIMO channel can be simplified to a parallel channel under the bit error ratio (BER) target constraint. The power is optimally allocated to each sub-channel to maximize the data rate. Simulation results show that the proposed adaptive modulation schemes can effectively improve the transmission rate of the systems under the BER target and constant optical power constraints. The proposed adaptive modulation schemes make use of the multiplexing gain of the MIMO techniques, and can further improve the spectrum efficiency of optical wireless systems.
基金supported by the National Natural Science Foundation of China(Grant Nos.61522109,61671253,61571037and 91738201)the Fundamental Research Funds for the Central Universities(No.2016JBZ006)+1 种基金the Natural Science Foundation of Jiangsu Province(Grant Nos.BK20150040and BK20171446)the Key Project of Natural Science Research of Higher Education Institutions of Jiangsu Province(No.15KJA510003)
文摘The fifth generation (5G) wireless communication is currently a hot research topic and wireless communication systems on high speed railways (HSR) are important applications of 5G technologies. Existing stud- ies about 5G wireless systems on high speed railways (HSR) often utilize ideal channel parameters and are usually based on simple scenarios. In this paper, we evaluate the down- link throughput of 5G HSR communication systems on three typical scenarios including urban, cutting and viaduct with three different channel estimators. The channel parameters of each scenario are generated with tapped delay line (TDL) models through ray-tracing sim- ulations, which can be considered as a good match to practical situations. The channel estimators including least square (LS), linear minimum mean square error (LMMSE), and our proposed historical information based ba- sis expansion model (HiBEM). We analyze the performance of the HiBEM estimator in terms of mean square error (MSE) and evaluate the system throughputs with different channel estimates over each scenario. Simulation results are then provided to corroborate our proposed studies. It is shown that our HiBEM estimator outperforms other estimators and that the sys-tem throughput can reach the highest point in the viaduct scenario.
基金supported by the Key Project of Chinese Ministry of Education(No.212168)
文摘To reduce the network deployment cost and provide voice, message and low rate data services in remote pastoral areas of Tibet effectively, an integrated wireless communication system utilizing MANET(Mobile Ad hoc Network) is proposed. The sparse mobile devices, assisted with the solar-powered multi-functional standing stations mainly on networking maintenance and routing arrangement, self-organize into a MANET. The topology of the standing stations is designed for networking robust and to simplify the routing method and energy strategy. Then in the OMNe T++(Objective Modular Network Test bed in C++) simulation, the energy consumption is analysis while adjusting routing with the different energy status of the standing stations. The result shows that the standing stations should adjust routing as well as control the mobile devices' activity level according to the energy states of the standing stations and their adjacent mobile devices.
基金This publication is an outcome of the R&D work undertaken project under the Visvesvaraya PhD Scheme(Grant No.Ph.D-MLA/4(16))of Ministry of Electronics&Information Technology,Government of India,being implemented by Digital India Corporation.
文摘The Optical Wireless Communication(OWC)offers the high capacity of optical fiber communication with the flexibility of wireless communication.Since it works in the optical region of the ElectroMagnetic(EM)spectrum,it guarantees safety and security which are critical in radio and microwave frequency communication.The principal objective of this paper is to analyze the indoor OWC systems on these guaranteed features,and safety and security are jointly denoted by the term green.The high obstacle impermeability of optical signals and their directivity strengthen the security of indoor OWC data transmission.The confidentiality and authenticity of optical wireless data can also be preserved with the Quantum Key Distribution(QKD).This paper provides a technological overview and a review of literature about the OWC system that helps to identify the challenges in the path of a ubiquitous deployment of green wireless communication systems.Significant advancements in the sources and detectors are discussed together with the coding,modulation and multiplexing techniques for making highly robust OWC links.The ubiquitous deployment of green OWC necessitates the development of optical transmitters and receivers,performance enhancement techniques,incorporation of uplink and energy harvesting abilities,and safety and security enhancement techniques.Hence,a special emphasis is placed on these aspects and their challenges towards the green implementation.Furthermore,the paper explores some significant indoor applications based on the OWC that have great impacts on the Next Generation Networks(NGN)and the Internet of Things(IoT).
文摘With the rapid development of wireless communications systems, different system standards are being merged. Operators take stringent measures to reduce Operational Expenditure (OPEX) and Capital Expenditure (CAPEX); and as a result, soft base stations supporting multiple standards become the evolutionary tend of wireless base stations. This paper introduces the background of soft base stations and analyzes their architecture design, system modules. The key technologies in system implementation and future directions are also presented.
文摘This paper investigates the jammerassisted multi-channel covert wireless communication(CWC)by exploiting the randomness of sub-channel selection to confuse the warden.In particular,we propose two sub-channel selection transmission schemes,named random sub-channel selection(RSS)scheme and maximum sub-channel selection(MSS)scheme,to enhance communication covertness.For each proposed scheme,we first derive closed-form expressions of the transmission outage probability(TOP),the average effective rate,and the minimum average detection error probability(DEP).Then,the average effective covert rate(ECR)is maximized by jointly optimizing the transmit power at the transmitter and the number of sub-channels.Numerical results show that there is an optimal value of the number of sub-channels that maximizes the average ECR.We also find that to achieve the maximum average ECR,a larger number of subchannels are needed facing a stricter covertness constraint.
基金supported by the National Natural Science Foundation of China (61302083, 61327806)the National Science and Technology Major Project (2012ZX03004005)
文摘Massive multiple-input multiple-output(MIMO) requires a large number(tens or hundreds) of base station antennas serving for much smaller number of terminals, with large gains in energy efficiency and spectral efficiency compared with traditional MIMO technology. Large scale antennas mean large scale radio frequency(RF) chains. Considering the plenty of power consumption and high cost of RF chains, antenna selection is necessary for Massive MIMO wireless communication systems in both transmitting end and receiving end. An energy efficient antenna selection algorithm based on convex optimization was proposed for Massive MIMO wireless communication systems. On the condition that the channel capacity of the cell is larger than a certain threshold, the number of transmit antenna, the subset of transmit antenna and servable mobile terminals(MTs) were jointly optimized to maximize energy efficiency. The joint optimization problem was proved in detail. The proposed algorithm is verified by analysis and numerical simulations. Good performance gain of energy efficiency is obtained comparing with no antenna selection.
基金the National Natural Science Foundationof China!(No.6 98310 30 )
文摘The concept of virtualization of wireless communication systems is based on the open and scalable hardware platform of software radios in the personal communication network. The base station is divided into four components according to their functions: antenna, IF, baseband, and control, which are connected by the ATM network. Virtualization provides great benefits such as fast handoff and easy realization of different macrodiversity algorithms. Macrodiversity can not be easily realized in conventional cellular systems. An exact analysis is presented for the performance of maximal ratio combining (MRC) macrodiversity in virtualized wireless communication systems. The results show that compared with soft handoff in CDMA systems, MRC can greatly increase the reverse link capacity.
文摘This paper focuses on the design and implementation of an active multibeam antenna system for massive MIMO applications in 5G wireless communications.The highly integrated active multibeam antenna system is designed and implemented at 5.8 GHz with 64 RF Channels and 256 antenna elements.The 64-channel highly integrated active multibeam antenna system provides a verification platform for digital beamforming algorithm and massive MIMO channel estimation for next generation wireless communications.
基金supported in part by the National Natural Science Foundation of China(Nos.62071441 and 61701464)in part by the Fundamental Research Funds for the Central Universities(No.202151006).
文摘This study explores the application of single photon detection(SPD)technology in underwater wireless optical communication(UWOC)and analyzes the influence of different modulation modes and error correction coding types on communication performance.The study investigates the impact of on-off keying(OOK)and 2-pulse-position modulation(2-PPM)on the bit error rate(BER)in single-channel intensity and polarization multiplexing.Furthermore,it compares the error correction performance of low-density parity check(LDPC)and Reed-Solomon(RS)codes across different error correction coding types.The effects of unscattered photon ratio and depolarization ratio on BER are also verified.Finally,a UWOC system based on SPD is constructed,achieving 14.58 Mbps with polarization OOK multiplexing modulation and 4.37 Mbps with polarization 2-PPM multiplexing modulation using LDPC code error correction.
基金supported by the National Natural Science Foundation of China(61674049,U19A2053)State Key Lab of ASIC and System(2019KF003)the Fundamental Research Funds for Central Universities(JZ2019HGTB0092)。
文摘Traditional magnetically coupled resonant wireless power transfer technology uses fixed distances between coils for research,to prevent fluctuations in the receiving voltage,and lead to reduce transmission efficiency.This paper proposes a closed-loop control wireless communication wireless power transfer system with a wearable four-coil structure to stabilize the receiving voltage fluctuation caused by changes in the displacement between the coils.Test results show that the system can provide stable receiving voltage,no matter how the distance between the transmitting coil and the receiving coil is changed.When the transmission distance is 20 mm,the power transfer efficiency of the system can reach 18.5%under the open-loop state,and the stimulus parameters such as the stimulation period and pulse width can be adjusted in real time through the personal computer terminal.
基金supported in part by National Key Research and Development Program of China(No.2022YFB2803002)National Natural Science Foundation of China(Nos.62235005,62127814,62225405,61975093,61927811,61991443,61925104 and 61974080)Collaborative Innovation Centre of Solid-State Lighting and Energy-Saving Electronics.
文摘This paper presents a wide-bandwidth back-illuminated modified uni-traveling-carrier photodiode(MUTC-PD)packaged with standard WR-5 rectangular waveguide for high-speed wireless communications.With optimized epitaxy structure and coplanar waveguide electrodes,the fabricated 4-μm-diameter PD exhibits ultra-flat frequency response and high saturation power.Integrated passive circuits including low-loss bias-tee and E-plane probe are designed to package the PD into a compact module with waveguide output.The packaged PD module has demonstrated a flat frequency response with fluctuations within±2.75 d B over a broadband of 140–220 GHz and a high saturated output power of-7.8 d Bm(166μW)at 140 GHz.For wireless communication applications,the packaged PD is used to implement 1-m free space transmission at carrier frequencies of 150.5 and 210.5 GHz,with transmission rates of 75 and 90 Gbps,respectively.
基金supported by the National Natura Science Foundation of China (NSFC), No.51607146China National Major Science and Technology Projects 2010ZX06004-013-04-02 and 2012ZX06002-017-02-01+1 种基金Sichuan Science and Technology Program,No.2018GZ0391Sichuan Hydropower Energy and power equipment technology Engineering Research Center, Xihua university, Chengdu 610039, China,No.SDNY2020-001
文摘In this study,a real-time rotor temperature monitoring system for large turbogenerators using SmartMesh IP wireless network communication technology was designed and tested.The system is capable of providing comprehensive,accurate,continuous,and reliable real-time temperature monitoring for turbogenerators.Additionally,it has demonstrated satisfactory results in a real-time monitoring test of the rotor temperature of various famous large-scale turbogenerators and giant nuclear power half-speed turbogenerators designed and manufactured in China.The development and application of this wireless temperature measurement system would aid in improving the intelligent operation quality,safety,and stability of China’s large turbine generators and even the entire power system.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.U1806202,61773010,and 61903207)the International Collaborative Research Project of Qilu University of Technology(Grant No.QLUTGJHZ2018020)Major Scientific and Technological Innovation Projects of Shandong Province,China(Grant Nos.2019JZZY010731 and 2020CXGC010901).
文摘As the competition for marine resources is increasingly fierce,the security of underwater acoustic communication has attracted a great deal of attention.The information and location of the communicating platform can be leaked during the traditional underwater acoustic communication technology.According to the unique advantages of chaos communication,we put forward a novel communication scheme using complex parameter modulation and the complex Lorenz system.Firstly,we design a feedback controller and parameter update laws in a complex-variable form with rigorous mathematical proofs(while many previous references on the real-variable form were only special cases in which the imaginary part was zero),which can be realized in practical engineering;then we design a new communication scheme employing parameter modulation.The main parameter spaces of the complex Lorenz system are discussed,then they are adopted in our communication scheme.We also find that there exist parametric attractors in the complex Lorenz system.We make numerical simulations in two channels for digital signals and the simulations verify our conclusions.
文摘An important problem in wireless communication networks (WCNs) is that they have a minimum number of resources, which leads to high-security threats. An approach to find and detect the attacks is the intrusion detection system (IDS). In this paper, the fuzzy lion Bayes system (FLBS) is proposed for intrusion detection mechanism. Initially, the data set is grouped into a number of clusters by the fuzzy clustering algorithm. Here, the Naive Bayes classifier is integrated with the lion optimization algorithm and the new lion naive Bayes (LNB) is created for optimally generating the probability measures. Then, the LNB model is applied to each data group, and the aggregated data is generated. After generating the aggregated data, the LNB model is applied to the aggregated data, and the abnormal nodes are identified based on the posterior probability function. The performance of the proposed FLBS system is evaluated using the KDD Cup 99 data and the comparative analysis is performed by the existing methods for the evaluation metrics accuracy and false acceptance rate (FAR). From the experimental results, it can be shown that the proposed system has the maximum performance, which shows the effectiveness of the proposed system in the intrusion detection.
基金supported by the National Science Foundation(NSF)(Grant No.EEC-1449501).
文摘The internet of the underground things(IoUT)is an emerging field that concerns connected underground sensing nodes and can find applications in various fields such as geotechnical engineering,precision agriculture,and search and rescue operations.The complex underground environment and multiphase nature of the soil pose challenges to wireless underground communication.Most existing studies on wireless underground communication focus on the use of electromagnetic waves.However,as a highly lossy material for electromagnetic waves,soil can limit the range and reliability of data transmission.Inspired by subterranean animals that rely on vibrations or seismic waves for underground communication,the prototype system developed in this study is based on vibration.This system includes a bioinspired vibrating source,a micro-electromechanical system(MEMS)accelerometer,a microcontroller,and a set of algorithms for encoding and decoding information.Specifically,the mole ratsinspired source is small in size,low in cost,and energy-efficient.An on-off-keying decoding algorithm enhanced with an error-correction algorithm is found to be robust in transmitting textual and imaginary information.With the current design,a maximum transmission bit rate of 16e17 bits per second and a transmission distance of 80 cm can be achieved.The bit error ratio is as low as 0.1%,demonstrating the robustness of the algorithms.The performance of the developed system shows that seismic waves produced by vibration can be used as an information carrier and can potentially be implemented in the IoUT.
基金supported by the Strategic Priority Research Program of the Chinese Academy Sciences under Grant XDA17040202,XDA13030403,XDA17020203。
文摘Aerostat platforms could serve as potential aerial platforms because of their low cost,long flight times,and easy load recovery.They are suitable for emergency communication,early warnings,Earth observations,and other fields.The air-ground communication link between an aerostat platform and the ground is the basic guarantee for aerostat measurement control and service transmission.In traditional aerostat applications,platform measurement control and service transmission usually use different links.The load and ground equipment are complex,and the energy,load,and size of the platform are greatly occupied.In this paper,we propose a Beidou-assisted air-ground communication ground for a near-space platform that uses Beidou's positioning and communication functions to provide tracking and guidance information for the ground station.An air-ground wireless communication mode integrating measurement control and service transmission is achieved.The flight test shows that the system can effectively meet the practical application requirements.