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
An equivalent microstrip antenna used in radio proximity fuse is presented.The design of this antenna is based on multilayer multipermittivity dielectric substrate which is analyzed by finite difference time domain(FD...An equivalent microstrip antenna used in radio proximity fuse is presented.The design of this antenna is based on multilayer multipermittivity dielectric substrate which is analyzed by finite difference time domain(FDTD) method.Equivalent iterative formula is modified in the condition of cylindrical coordinate system.The mixed substrate which contains two kinds of media(one of them is air)takes the place of original single substrate.The results of equivalent antenna simulation show that the resonant frequency of equivalent antenna is similar to that of the original antenna.The validity of analysis can be validated by means of antenna resonant frequency formula.Two antennas have same radiation pattern and similar gain.This method can be used to reduce the weight of antenna,which is significant to the design of missile-borne antenna.展开更多
The characteristics of a cylindrical conformal microstrip patch antenna are analyzed by using the characteristic-based time domain （CBTD） method. A governing equation in the cylindrical coordinate system is formulat...The characteristics of a cylindrical conformal microstrip patch antenna are analyzed by using the characteristic-based time domain （CBTD） method. A governing equation in the cylindrical coordinate system is formulated directly to facilitate the analysis of cylindrically conformal microstrip patch antennas. The algorithm has second-order accuracy both in time and space domain and has the potential to eliminate the spurious wave reflection from the numerical boundaries of the computational domain, Numerical results demonstrate the important merits and accuracy of the proposed technique in computational electromagnetics,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.6111168)
文摘An equivalent microstrip antenna used in radio proximity fuse is presented.The design of this antenna is based on multilayer multipermittivity dielectric substrate which is analyzed by finite difference time domain(FDTD) method.Equivalent iterative formula is modified in the condition of cylindrical coordinate system.The mixed substrate which contains two kinds of media(one of them is air)takes the place of original single substrate.The results of equivalent antenna simulation show that the resonant frequency of equivalent antenna is similar to that of the original antenna.The validity of analysis can be validated by means of antenna resonant frequency formula.Two antennas have same radiation pattern and similar gain.This method can be used to reduce the weight of antenna,which is significant to the design of missile-borne antenna.
文摘The characteristics of a cylindrical conformal microstrip patch antenna are analyzed by using the characteristic-based time domain （CBTD） method. A governing equation in the cylindrical coordinate system is formulated directly to facilitate the analysis of cylindrically conformal microstrip patch antennas. The algorithm has second-order accuracy both in time and space domain and has the potential to eliminate the spurious wave reflection from the numerical boundaries of the computational domain, Numerical results demonstrate the important merits and accuracy of the proposed technique in computational electromagnetics,
