Antenna is very crucial to radiotelemetry capsules which can measure the physiological parameters of the gastroin- testinal (GI) tract. The objective of this paper is to design a novel spiral slots microstrip patch an...Antenna is very crucial to radiotelemetry capsules which can measure the physiological parameters of the gastroin- testinal (GI) tract. The objective of this paper is to design a novel spiral slots microstrip patch antenna for the radiotelemetry capsules communicating with external recorder at 915 MHz located in ISM (Industry, Science, and Medical) bands. The microstrip patch antenna is designed and evaluated using the finite-difference time-domain (FDTD) method. Return loss characteristics and the effect of the human body on resonant frequency are analyzed, and the performances of radiation patterns at different positions of the human alimentary tract are also estimated. Finally, specific absorption rate (SAR) computations are performed, and the peak 1-g and 10-g SAR values are calculated. According to the peak SAR values, the maximum delivered power for the designed antenna was found so that the SAR values of the antenna satisfy the ANSI (American National Standards Institute) limitations.展开更多
Aiming at developing a node scheduling protocol for sensor networks with fewer active nodes,we propose a coordinated node scheduling protocol based on the presentation of a solution and its optimization to determine w...Aiming at developing a node scheduling protocol for sensor networks with fewer active nodes,we propose a coordinated node scheduling protocol based on the presentation of a solution and its optimization to determine whether a node is redundant.The proposed protocol can reduce the number of working nodes by turning off as many redundant nodes as possible without degrading the coverage and connectivity.The simulation result shows that our protocol outperforms the peer with respect to the working node number and dynamic coverage percentage.展开更多
A wavelength division multiplexer based on curved polymer planar waveguide is proposed. According to the coupled modetheory and the waveguide structure, the performance of the curved waveguide coupler (CWC) is analyze...A wavelength division multiplexer based on curved polymer planar waveguide is proposed. According to the coupled modetheory and the waveguide structure, the performance of the curved waveguide coupler (CWC) is analyzed. The results showthat CWC can accommodate wider multiplexing bandwidth than parallel straight waveguide coupler (SWC) due to thecompensation effect of the effective coupling length. The two variables, curvature radius and minimum spacing, increasethe design flexibility of the waveguide device. A 4-channel wavelength division multiplexing (WDM) system based onCWC is designed. The deviation of the center wavelength, due to the errors of curvature radius and minimum spacingduring fabrication process, is investigated. The smaller the curvature radius and the minimum spacing are, the larger thecentral wavelength deviation caused by the error of the curvature radius and the minimum spacing is, which provides someuseful theoretical basis for the design and the fabrication of polymer waveguide devices.展开更多
A novel MEMS device boning system is presented. Aiming at the high velocity, high precision and high flexibility requirements, a novel manipulator of planar parallel structure is developed to substitute ordinary X-Y t...A novel MEMS device boning system is presented. Aiming at the high velocity, high precision and high flexibility requirements, a novel manipulator of planar parallel structure is developed to substitute ordinary X-Y table. In addition, the machine vision is implemented to improve the system＇ s flexibility. The initial angular positions of the joints are estimated by the extended Kalman filter algorithm. As a resuh, the manipulator＇s absolute locating accuracy in its workspace is guaranteed indirectly. For any MEMS device, the bonding system itself can be used as measurement equipment to create the device＇ s geometry model, which is the base to do off-line programming. A quite ideal trade-off between the system＇ s flexibility and efficiency is got. Finally, some verified motion specification of the manipulator, the bonding experimental results and the verified qualities of the bonded devices are provided.展开更多
基金Project (No. 2006AA04Z368) supported by the Hi-Tech Researchand Development Program (863) of China
文摘Antenna is very crucial to radiotelemetry capsules which can measure the physiological parameters of the gastroin- testinal (GI) tract. The objective of this paper is to design a novel spiral slots microstrip patch antenna for the radiotelemetry capsules communicating with external recorder at 915 MHz located in ISM (Industry, Science, and Medical) bands. The microstrip patch antenna is designed and evaluated using the finite-difference time-domain (FDTD) method. Return loss characteristics and the effect of the human body on resonant frequency are analyzed, and the performances of radiation patterns at different positions of the human alimentary tract are also estimated. Finally, specific absorption rate (SAR) computations are performed, and the peak 1-g and 10-g SAR values are calculated. According to the peak SAR values, the maximum delivered power for the designed antenna was found so that the SAR values of the antenna satisfy the ANSI (American National Standards Institute) limitations.
基金the National Natural Science Foundation of China(Grant No.60533110 and No.90604013)the Scientific Research Foundation of Harbin Institute of Technology(Grant No. HIT2002.74)
文摘Aiming at developing a node scheduling protocol for sensor networks with fewer active nodes,we propose a coordinated node scheduling protocol based on the presentation of a solution and its optimization to determine whether a node is redundant.The proposed protocol can reduce the number of working nodes by turning off as many redundant nodes as possible without degrading the coverage and connectivity.The simulation result shows that our protocol outperforms the peer with respect to the working node number and dynamic coverage percentage.
基金This work was partially supported by the National Natural ScienceFoundation of China (No.60577014)the Young Teacher Cultiva-tion Foundation of Dalian University of Technology (No. 893210)the Doctor Start-up Foundation of Dalian University of Tech-nology (No. 893322).
文摘A wavelength division multiplexer based on curved polymer planar waveguide is proposed. According to the coupled modetheory and the waveguide structure, the performance of the curved waveguide coupler (CWC) is analyzed. The results showthat CWC can accommodate wider multiplexing bandwidth than parallel straight waveguide coupler (SWC) due to thecompensation effect of the effective coupling length. The two variables, curvature radius and minimum spacing, increasethe design flexibility of the waveguide device. A 4-channel wavelength division multiplexing (WDM) system based onCWC is designed. The deviation of the center wavelength, due to the errors of curvature radius and minimum spacingduring fabrication process, is investigated. The smaller the curvature radius and the minimum spacing are, the larger thecentral wavelength deviation caused by the error of the curvature radius and the minimum spacing is, which provides someuseful theoretical basis for the design and the fabrication of polymer waveguide devices.
基金Supported by the High Technology Research and Development Programme of China （No. 2003AA404060） and the National Natural Science Foundation of China （No.60405008）.
文摘A novel MEMS device boning system is presented. Aiming at the high velocity, high precision and high flexibility requirements, a novel manipulator of planar parallel structure is developed to substitute ordinary X-Y table. In addition, the machine vision is implemented to improve the system＇ s flexibility. The initial angular positions of the joints are estimated by the extended Kalman filter algorithm. As a resuh, the manipulator＇s absolute locating accuracy in its workspace is guaranteed indirectly. For any MEMS device, the bonding system itself can be used as measurement equipment to create the device＇ s geometry model, which is the base to do off-line programming. A quite ideal trade-off between the system＇ s flexibility and efficiency is got. Finally, some verified motion specification of the manipulator, the bonding experimental results and the verified qualities of the bonded devices are provided.
