A theoretical model is developed for calculating the eigenmodes of the multi-gap resonant cavity. The structure of concern is a kind of ladder-type circuit, offering the advantages of easy fabrication, high characteri...A theoretical model is developed for calculating the eigenmodes of the multi-gap resonant cavity. The structure of concern is a kind of ladder-type circuit, offering the advantages of easy fabrication, high characteristic impedance (R/Q), and thermal capacity in the millimeter wave to THz regime. The eigenfunction expansion method is used to establish the field expressions for the gaps and the coupling region. Then, the match conditions at the interface are employed, which leads to a group of complicate boundary equations in the form of an infinite series. To facilitate the mathematical treatments and perform a highly efficient calculation, these boundary equations are transformed into the algebraic forms through the matrix representations. Finally, the concise dispersion equation is obtained. The roots of the dispersion equation include both the axial modes in the gaps, which include the fundamental and the high-order modes, and the cavity modes in the coupling region. Extensive numerical results are presented and the behaviors of the multi-gap resonant cavity are examined.展开更多
The paper had analyzed the necessity and feasibility for the protection and utilization of urban ecologically sensitive areas, proposed planning urban ecologically sensitive areas reasonably and combining ecological p...The paper had analyzed the necessity and feasibility for the protection and utilization of urban ecologically sensitive areas, proposed planning urban ecologically sensitive areas reasonably and combining ecological protection with development construction. Guiding the healthy and ordered development of urban spaces was the key part and important approach to realize ecological cities. The guiding thought for development construction of ecological cities had been discussed, which was conducting laddered development according to the location and coverage of urban ecologically sensitive areas and protection grades of these sensitive areas. Then, it had proposed four kinds of protection and construction modes, which were tourism leisure green lands, relevant expositions, industrial areas and new city groups, and which had been analyzed by combining with successful cases, so as to provide feasible win-win development strategies of ecology and economy for the planning of urban ecologically sensitive areas in the future.展开更多
A new technique using signal flow graph for conversion of ladder based filter into CFOA based filter has been proposed. The proposed technique converts the existing LC ladder based filter into CFOA in low pass and hig...A new technique using signal flow graph for conversion of ladder based filter into CFOA based filter has been proposed. The proposed technique converts the existing LC ladder based filter into CFOA in low pass and high pass configuration. The design of low pass filter and high pass filter has been realized using the proposed technique. The proposed configuration is implemented using CFOA as an active device and all the capacitors are grounded. Simulation has been carried out using simulation software I-cap. The simulation results have been demonstrated and discussed.展开更多
A new technique for the conversion of ladder based filter into CFOA based filter has been proposed. The technique uses signal flow graph and converts the existing LC ladder based filter into band pass & band stop ...A new technique for the conversion of ladder based filter into CFOA based filter has been proposed. The technique uses signal flow graph and converts the existing LC ladder based filter into band pass & band stop configurations. The design of band pass and band stop filter has been realized using the proposed technique. The proposed configuration is implemented using CFOA as an active device and all the capacitors are grounded. CFOA based circuits have greater linearity, high dynamic rate, high slew rate and high signal bandwidth. Simulation has been carried out using simulation software P Spice (v10.1). The simulation results have been demonstrated and discussed.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61222110 and 60971073)
文摘A theoretical model is developed for calculating the eigenmodes of the multi-gap resonant cavity. The structure of concern is a kind of ladder-type circuit, offering the advantages of easy fabrication, high characteristic impedance (R/Q), and thermal capacity in the millimeter wave to THz regime. The eigenfunction expansion method is used to establish the field expressions for the gaps and the coupling region. Then, the match conditions at the interface are employed, which leads to a group of complicate boundary equations in the form of an infinite series. To facilitate the mathematical treatments and perform a highly efficient calculation, these boundary equations are transformed into the algebraic forms through the matrix representations. Finally, the concise dispersion equation is obtained. The roots of the dispersion equation include both the axial modes in the gaps, which include the fundamental and the high-order modes, and the cavity modes in the coupling region. Extensive numerical results are presented and the behaviors of the multi-gap resonant cavity are examined.
文摘The paper had analyzed the necessity and feasibility for the protection and utilization of urban ecologically sensitive areas, proposed planning urban ecologically sensitive areas reasonably and combining ecological protection with development construction. Guiding the healthy and ordered development of urban spaces was the key part and important approach to realize ecological cities. The guiding thought for development construction of ecological cities had been discussed, which was conducting laddered development according to the location and coverage of urban ecologically sensitive areas and protection grades of these sensitive areas. Then, it had proposed four kinds of protection and construction modes, which were tourism leisure green lands, relevant expositions, industrial areas and new city groups, and which had been analyzed by combining with successful cases, so as to provide feasible win-win development strategies of ecology and economy for the planning of urban ecologically sensitive areas in the future.
文摘A new technique using signal flow graph for conversion of ladder based filter into CFOA based filter has been proposed. The proposed technique converts the existing LC ladder based filter into CFOA in low pass and high pass configuration. The design of low pass filter and high pass filter has been realized using the proposed technique. The proposed configuration is implemented using CFOA as an active device and all the capacitors are grounded. Simulation has been carried out using simulation software I-cap. The simulation results have been demonstrated and discussed.
文摘A new technique for the conversion of ladder based filter into CFOA based filter has been proposed. The technique uses signal flow graph and converts the existing LC ladder based filter into band pass & band stop configurations. The design of band pass and band stop filter has been realized using the proposed technique. The proposed configuration is implemented using CFOA as an active device and all the capacitors are grounded. CFOA based circuits have greater linearity, high dynamic rate, high slew rate and high signal bandwidth. Simulation has been carried out using simulation software P Spice (v10.1). The simulation results have been demonstrated and discussed.