This paper introduces a novel verification development platform for the passive UHF RFID tag,which is compatible with the ISO/IEC 18000-6B standard,operating in the 915MHz ISM band. This platform efficiently reduces t...This paper introduces a novel verification development platform for the passive UHF RFID tag,which is compatible with the ISO/IEC 18000-6B standard,operating in the 915MHz ISM band. This platform efficiently reduces the design and development time and cost, and implements a fast prototype design of the passive UHF RFID tag. It includes the RFID analog front end and the tag control logic, which is implemented in an Altera ACEX FPGA. The RFID analog front end, which is fabricated using a Chartered 0.35μm two-poly four-metal CMOS process, contains a local oscillator, power on reset circuit, matching network and backscatter, rectifier, regu- lator,AM demodulator, etc. The platform achieves rapid, flexible and efficient verification and development, and can also be fit for other RFID standards after changing the tag control logic in FPGA.展开更多
According to the characteristics of gravity passive navigation, this paper presents a novel gravity passive navigation system （GPNS）, which consists of the rate azimuth platform （RAP）, gravity sensor, digitally st...According to the characteristics of gravity passive navigation, this paper presents a novel gravity passive navigation system （GPNS）, which consists of the rate azimuth platform （RAP）, gravity sensor, digitally stored gravity maps, depth sensor and relative log. The algorithm of rate azimuth platform inertial navigation system, error state-space equations, measurement equations and GPNS optimal filter are described. In view of the measurements made by an onboard gravity sensor the Eotvos effect is introduced in the gravity measurement equation of a GPNS optimal filter. A GPNS is studied with the Matlab/Simulink tools; simulation results demonstrate that a GPNS has small errors in platform attitude and position. Because the inertial navigation platform is the rate azimuth platform in the GPNS and gravity sensor is mounted on the rate azimuth platform, the cost of the GPNS is lower than existing GPNS＇s and according to the above results the GPNS meets the need to maintain accuracy navigation for underwater vehicles over long intervals.展开更多
The functions and characteristics of software radio are discussed. Using techniques and method of software radio, the concept and advantages of a new kind of radio fuze, software radio fuze, are analysed. Several kind...The functions and characteristics of software radio are discussed. Using techniques and method of software radio, the concept and advantages of a new kind of radio fuze, software radio fuze, are analysed. Several kinds of hardware platform structures of the software radio fuze are studied and the key techniques are analysed. The software radio fuze will become the most promising radio fuze techniques in 21st century.展开更多
In this paper,we propose a wireless channel testing method and construct the test platform for the Gbps broadband wireless system.The proposed method is implemented to evaluate the transmission performance according t...In this paper,we propose a wireless channel testing method and construct the test platform for the Gbps broadband wireless system.The proposed method is implemented to evaluate the transmission performance according to the acquired field test results.The results have shown that the proposed channel test algorithm is valid and efficient,which can continuously show the variation of system throughput,frame loss rate and latency.展开更多
Two-way packet exchange synchronization scheme has been widely used in wireless sensor networks. However, due to the fact that its synchronization error accumulates rapidly over hop count, its applications are greatly...Two-way packet exchange synchronization scheme has been widely used in wireless sensor networks. However, due to the fact that its synchronization error accumulates rapidly over hop count, its applications are greatly restricted. In this paper, the factors that cause the accumulation of synchronization error over hop count are investigated. Theoretical analysis shows that two factors including the clock drift and the asymmetry of two-way packet exchange, have distinct influences on synchronization error between two adjacent nodes. Further, the clock frequency order along synchronization path is found to be vital to the accumulation of synchronization error. The above three factors jointly determine the accumulation of synchronization error over hop count in wireless network. Theoretic results are also verified by three fine-grained experiments on wireless sensor network testbed. The conclusions can be used to decrease synchronization error for large-scale wireless network by careful network deployment.展开更多
Multiple-Input Multiple-Output （MIMO） and Orthogonal Frequency Division Multiplexing （OFDM） have been widely accepted as key techniques of the current and future wireless communication systems. In this paper, an o...Multiple-Input Multiple-Output （MIMO） and Orthogonal Frequency Division Multiplexing （OFDM） have been widely accepted as key techniques of the current and future wireless communication systems. In this paper, an open access MIMO testbed is presented, on which the researchers can demonstrate and evaluate their baseband algorithms over the real wireless channel, without knowing much details about the hardware of the testbed. Moreover, an IEEE 802.11n transmission scheme is implemented as a design example to validate this testbed as well as demonstrate the transmission characteristics of MIMO-OFDM.展开更多
This paper introduces the research progress on the cognition flow in the National Basic Research Program of China(973 Program)under Grant No. 2009CB320400 "Research on Basic Theories and Key Technologies of Cogni...This paper introduces the research progress on the cognition flow in the National Basic Research Program of China(973 Program)under Grant No. 2009CB320400 "Research on Basic Theories and Key Technologies of Cognitive Radio Networks". We present the motivation behind the proposal of the concept of cognition flow, provide the definition, discuss the features, behaviours, representations, mathematical models, and the functions of cognition flow in Cognitive Radio Networks(CRNs). We also analyse how the cognition flow promotes the convergence of heterogeneous networks.Our group also constructed the test platform to verify the usefulness of cognition flow. The results that were simulated by computers and tested on the platform both confirm that cognition flow can realise efficient interaction of cognitive information among heterogeneous networks in CRNs, which contributes to the seamless convergence of heterogeneous networks,and significantly improves the spectrum efficiency and users' Quality of Experience(QoE).展开更多
In order to achieve an automatic leveling function for work platforms of aerial vehicles with mixed-booms( MAV) in full elevating domain,an auto-leveling mechanism for the platform is proposed based on a control metho...In order to achieve an automatic leveling function for work platforms of aerial vehicles with mixed-booms( MAV) in full elevating domain,an auto-leveling mechanism for the platform is proposed based on a control method of booms-constraint,where mixed-boom structures and elevating characteristics are considered. Three models of constraint strategies include non-constraint model,elevating constraint model and lowering constraint model,which is designed to meet the leveling requirements in full working extent. Through the hydro-mechatronic unified modeling,a virtual prototype model is set up based on the auto-leveling mechanism,and leveling performances of the platform are studied during booms elevating to the maximum working height and extent. Simulation results show that the control method of booms-constraint can realize auto-leveling of the platform under two typical working conditions,meanwhile a leveling deviation appears at the constrained point,but the platform inclination is adjusted in the permissible range. The control method does not only restrict booms' freedom elevating to a certain extent,but also impacts the booms extending to the maximum working range. Experimental results verify that the auto-leveling mechanism based on booms-constraint control is valid and rational,which provides an effective technology approach for development of the platform leveling of MAV.展开更多
文摘This paper introduces a novel verification development platform for the passive UHF RFID tag,which is compatible with the ISO/IEC 18000-6B standard,operating in the 915MHz ISM band. This platform efficiently reduces the design and development time and cost, and implements a fast prototype design of the passive UHF RFID tag. It includes the RFID analog front end and the tag control logic, which is implemented in an Altera ACEX FPGA. The RFID analog front end, which is fabricated using a Chartered 0.35μm two-poly four-metal CMOS process, contains a local oscillator, power on reset circuit, matching network and backscatter, rectifier, regu- lator,AM demodulator, etc. The platform achieves rapid, flexible and efficient verification and development, and can also be fit for other RFID standards after changing the tag control logic in FPGA.
文摘According to the characteristics of gravity passive navigation, this paper presents a novel gravity passive navigation system （GPNS）, which consists of the rate azimuth platform （RAP）, gravity sensor, digitally stored gravity maps, depth sensor and relative log. The algorithm of rate azimuth platform inertial navigation system, error state-space equations, measurement equations and GPNS optimal filter are described. In view of the measurements made by an onboard gravity sensor the Eotvos effect is introduced in the gravity measurement equation of a GPNS optimal filter. A GPNS is studied with the Matlab/Simulink tools; simulation results demonstrate that a GPNS has small errors in platform attitude and position. Because the inertial navigation platform is the rate azimuth platform in the GPNS and gravity sensor is mounted on the rate azimuth platform, the cost of the GPNS is lower than existing GPNS＇s and according to the above results the GPNS meets the need to maintain accuracy navigation for underwater vehicles over long intervals.
文摘The functions and characteristics of software radio are discussed. Using techniques and method of software radio, the concept and advantages of a new kind of radio fuze, software radio fuze, are analysed. Several kinds of hardware platform structures of the software radio fuze are studied and the key techniques are analysed. The software radio fuze will become the most promising radio fuze techniques in 21st century.
基金supported by International Scientific and Technological Cooperation Program from MOST.(No.S2010GR0902)the Science and Technology Innovation Program of Shanghai(No.09dz2201100)+1 种基金Equipment Functional Development of Technological Innovation Projects from CAS(No.YG2010060)Research Fund of National Mobile Communications Research Laboratory,Southeast University(No.2009A04)
文摘In this paper,we propose a wireless channel testing method and construct the test platform for the Gbps broadband wireless system.The proposed method is implemented to evaluate the transmission performance according to the acquired field test results.The results have shown that the proposed channel test algorithm is valid and efficient,which can continuously show the variation of system throughput,frame loss rate and latency.
基金Supported by the National Natural Science Foundation of China （61003307, 61173132, 60803159）,the Basic Disciplines Research Foundation of China University of Petroleum, Beijing （JCXK-2010-01）, Key Laboratory of Computer System and Architecture, ICT,CAS（ICT-ARCH200901）, and the Open Laboratory for the Internet Fundamental Technology, China Intemet Network Information Center（2012-N03）
文摘Two-way packet exchange synchronization scheme has been widely used in wireless sensor networks. However, due to the fact that its synchronization error accumulates rapidly over hop count, its applications are greatly restricted. In this paper, the factors that cause the accumulation of synchronization error over hop count are investigated. Theoretical analysis shows that two factors including the clock drift and the asymmetry of two-way packet exchange, have distinct influences on synchronization error between two adjacent nodes. Further, the clock frequency order along synchronization path is found to be vital to the accumulation of synchronization error. The above three factors jointly determine the accumulation of synchronization error over hop count in wireless network. Theoretic results are also verified by three fine-grained experiments on wireless sensor network testbed. The conclusions can be used to decrease synchronization error for large-scale wireless network by careful network deployment.
文摘Multiple-Input Multiple-Output （MIMO） and Orthogonal Frequency Division Multiplexing （OFDM） have been widely accepted as key techniques of the current and future wireless communication systems. In this paper, an open access MIMO testbed is presented, on which the researchers can demonstrate and evaluate their baseband algorithms over the real wireless channel, without knowing much details about the hardware of the testbed. Moreover, an IEEE 802.11n transmission scheme is implemented as a design example to validate this testbed as well as demonstrate the transmission characteristics of MIMO-OFDM.
基金supported by the National Basic Research Program of China(973 Program)under Grant No.2009CB320400the National Natural Science Foundation of China under Grants No.61101117,No.61171099+2 种基金the National Key Scientific and Technological Project of China under Grant No,2012ZX03003-007the Natural Science Foundation of Jiangxi under Grant No.20132BAB201018the Fundamental Research Funds for the Central Universities under Grant No.BUPT2012RC0112
文摘This paper introduces the research progress on the cognition flow in the National Basic Research Program of China(973 Program)under Grant No. 2009CB320400 "Research on Basic Theories and Key Technologies of Cognitive Radio Networks". We present the motivation behind the proposal of the concept of cognition flow, provide the definition, discuss the features, behaviours, representations, mathematical models, and the functions of cognition flow in Cognitive Radio Networks(CRNs). We also analyse how the cognition flow promotes the convergence of heterogeneous networks.Our group also constructed the test platform to verify the usefulness of cognition flow. The results that were simulated by computers and tested on the platform both confirm that cognition flow can realise efficient interaction of cognitive information among heterogeneous networks in CRNs, which contributes to the seamless convergence of heterogeneous networks,and significantly improves the spectrum efficiency and users' Quality of Experience(QoE).
基金Supported by the National Natural Science Foundation of China(No.51509006)National Key Technology R&D Program(No.2015BAF07B08)Fundamental Research Funds for the Central Universities of Chang’an University(No.310825161008)
文摘In order to achieve an automatic leveling function for work platforms of aerial vehicles with mixed-booms( MAV) in full elevating domain,an auto-leveling mechanism for the platform is proposed based on a control method of booms-constraint,where mixed-boom structures and elevating characteristics are considered. Three models of constraint strategies include non-constraint model,elevating constraint model and lowering constraint model,which is designed to meet the leveling requirements in full working extent. Through the hydro-mechatronic unified modeling,a virtual prototype model is set up based on the auto-leveling mechanism,and leveling performances of the platform are studied during booms elevating to the maximum working height and extent. Simulation results show that the control method of booms-constraint can realize auto-leveling of the platform under two typical working conditions,meanwhile a leveling deviation appears at the constrained point,but the platform inclination is adjusted in the permissible range. The control method does not only restrict booms' freedom elevating to a certain extent,but also impacts the booms extending to the maximum working range. Experimental results verify that the auto-leveling mechanism based on booms-constraint control is valid and rational,which provides an effective technology approach for development of the platform leveling of MAV.
