The RPS method,which integrates the real numerical solution, the perturbation solution and the shooting solution reasonably,can obtain the complex solution of a slab waveguide with small gain/loss regions without sear...The RPS method,which integrates the real numerical solution, the perturbation solution and the shooting solution reasonably,can obtain the complex solution of a slab waveguide with small gain/loss regions without searching the root in the entire complex plan.A revision to the RPS method is presented so that it can deal with the waveguide including large gain/loss regions.The application indicated that the simulation results are precise.展开更多
With the development of long range missile early warning radar,MMW phased array antenna is strongly needed. The phase shifter (PS) with high power capability and low insertion loss is a key technology in this kind of ...With the development of long range missile early warning radar,MMW phased array antenna is strongly needed. The phase shifter (PS) with high power capability and low insertion loss is a key technology in this kind of radar. Ferrite dielectric waveguide is introduced in this paper to manufacture PS,the cross section can be enlarged to 4 times of that of the conventional PS,which facilitates the engineering realization with reduced insertion loss. A novel vector base function of Galerkin method is proposed in calculating the eigenvalue of ferrite dielectric waveguide. The field distribution of main mode,power density and efficiency of 94 GHz difference phase shifter are also given.展开更多
A new structure of dielectric waveguide for millimeter waveband namedgroove nonradiative dielectric(GNRD)waveguide and a leakywave antenna based on thisstructure are developed in this paper.The GNRD structure overcome...A new structure of dielectric waveguide for millimeter waveband namedgroove nonradiative dielectric(GNRD)waveguide and a leakywave antenna based on thisstructure are developed in this paper.The GNRD structure overcomes the difficulty of as-sembling precisely the dielectric strip in the nonradiative dielectric(NRD)structure.Thedispersion characteristics of the GNRD waveguide,and the propagation and radiationcharacteristics of the GNRD leakywave antcnna have been analysed by the use of thetransverse rcsonance mcthod.The theoretical results are in good agreement with the exper-imental data.展开更多
The dispersion characteristics of a class of closed dielectric waveguides are investigated by themethod which combines the building-block approach of multimode network theory with the rigorous modematching procedure.S...The dispersion characteristics of a class of closed dielectric waveguides are investigated by themethod which combines the building-block approach of multimode network theory with the rigorous modematching procedure.Several numerical examples for difrerent guiding structures have been given by the ap-proach.The same structures are also analyzed with the finite element method and the EDC method forcomparison.The calculations show that the present approach yields as highly accurate results as the finite ele-ment method while almost retaining the simplicity of the EDC method,and justify the utility of the presentmethod.展开更多
The anisotropic Perfectly Matched Layer(PML) absorbing boundary condition is implemented in a 2-D finite element formulation to solve dielectric waveguide discontinuity problems. The choice of parameters of anisotropi...The anisotropic Perfectly Matched Layer(PML) absorbing boundary condition is implemented in a 2-D finite element formulation to solve dielectric waveguide discontinuity problems. The choice of parameters of anisotropic PML has been investigated. Using the boundary truncating technique, the solution process of Finite-Element Method (FEM) has been greatly simplified compared with other hybrid methods. The required computational resources have also significantly declined since the anisotropic PML interface can be placed much closer to the scatterer compared to other well known artificial boundary.展开更多
Several technical problems of numerical method in TLM procedures arediscussed.The bandwidth of single mode in four kinds of dielectric slab loaded rect-angular waveguides is investigated,and the optimum bandwidth whic...Several technical problems of numerical method in TLM procedures arediscussed.The bandwidth of single mode in four kinds of dielectric slab loaded rect-angular waveguides is investigated,and the optimum bandwidth which is related tothe dimensions and dielectric constants is obtained.These results are useful to the de-sign of dielectric slab loaded rectangular waveguide.展开更多
The equivalent filter modeling of a rectangular dielectric post in a rectangular waveguide is obtained through the variational expression of input impedance. The reflection coefficient expressed in components of netwo...The equivalent filter modeling of a rectangular dielectric post in a rectangular waveguide is obtained through the variational expression of input impedance. The reflection coefficient expressed in components of network is in good agreement with the results given by K. Siakavara, et al. (1991), The method can be applied to design filter.展开更多
The guided and leaky modes of a planar dielectric waveguide are eigensolutions of a singular Sturm-Liouville problem. The modes are the roots of a characteristicfunction which can be found with several methods that ha...The guided and leaky modes of a planar dielectric waveguide are eigensolutions of a singular Sturm-Liouville problem. The modes are the roots of a characteristicfunction which can be found with several methods that have been introduced in thepast. However, the evaluation of the characteristic function suffers from numericalinstabilities, and hence it is often difficult to find all modes in a given range. Here anew variational formulation is introduced, which, after discretization, leads either to aquadratic or a quartic eigenvalue problem. The modes can be computed with standardsoftware for polynomial eigenproblems. Numerical examples show that the method isnumerically stable and guarantees a complete set of solutions.展开更多
From the mode-marching method,by doing some transforms and derivations,the scatteringand propagation integral equations for solving the problems of discontinuous dielectric structure are ob-tained.The necessary and su...From the mode-marching method,by doing some transforms and derivations,the scatteringand propagation integral equations for solving the problems of discontinuous dielectric structure are ob-tained.The necessary and sufficient condition for the existence of solution of propagating equations is giv-en.It is really the dispersion equation of the dielectric structure.As an example,a succinct solution ofone-step discontinuous dielectric structure is derived.展开更多
We study the WKB dispersion equation in non-uniform optical waveguide.There are three methods given in this paper:(1) method of Airy function;(2)method of connection formula;and(3) method of phase shift.At last we mak...We study the WKB dispersion equation in non-uniform optical waveguide.There are three methods given in this paper:(1) method of Airy function;(2)method of connection formula;and(3) method of phase shift.At last we make some remarks.展开更多
A glass based slab waveguide, coated with a thin patterned high dielectric overlay, is configured into a refractive index sensor. The asymmetric nature of the waveguide configuration is exploited by keeping the mode i...A glass based slab waveguide, coated with a thin patterned high dielectric overlay, is configured into a refractive index sensor. The asymmetric nature of the waveguide configuration is exploited by keeping the mode in the slab waveguide while enhancing the field level in the overlay-superstrate. The sensor's response is examined using the FDTD simulation technique. A sensitivity of up to one part in 105 in the index of refraction discrimination is determined. The nature of the sensor ensures optical fibre compatibility, requires sub-μL sample volumes and provides a high resolution.展开更多
文摘The RPS method,which integrates the real numerical solution, the perturbation solution and the shooting solution reasonably,can obtain the complex solution of a slab waveguide with small gain/loss regions without searching the root in the entire complex plan.A revision to the RPS method is presented so that it can deal with the waveguide including large gain/loss regions.The application indicated that the simulation results are precise.
文摘With the development of long range missile early warning radar,MMW phased array antenna is strongly needed. The phase shifter (PS) with high power capability and low insertion loss is a key technology in this kind of radar. Ferrite dielectric waveguide is introduced in this paper to manufacture PS,the cross section can be enlarged to 4 times of that of the conventional PS,which facilitates the engineering realization with reduced insertion loss. A novel vector base function of Galerkin method is proposed in calculating the eigenvalue of ferrite dielectric waveguide. The field distribution of main mode,power density and efficiency of 94 GHz difference phase shifter are also given.
文摘A new structure of dielectric waveguide for millimeter waveband namedgroove nonradiative dielectric(GNRD)waveguide and a leakywave antenna based on thisstructure are developed in this paper.The GNRD structure overcomes the difficulty of as-sembling precisely the dielectric strip in the nonradiative dielectric(NRD)structure.Thedispersion characteristics of the GNRD waveguide,and the propagation and radiationcharacteristics of the GNRD leakywave antcnna have been analysed by the use of thetransverse rcsonance mcthod.The theoretical results are in good agreement with the exper-imental data.
基金Supported by the National Nature Seience Foundation of China
文摘The dispersion characteristics of a class of closed dielectric waveguides are investigated by themethod which combines the building-block approach of multimode network theory with the rigorous modematching procedure.Several numerical examples for difrerent guiding structures have been given by the ap-proach.The same structures are also analyzed with the finite element method and the EDC method forcomparison.The calculations show that the present approach yields as highly accurate results as the finite ele-ment method while almost retaining the simplicity of the EDC method,and justify the utility of the presentmethod.
文摘The anisotropic Perfectly Matched Layer(PML) absorbing boundary condition is implemented in a 2-D finite element formulation to solve dielectric waveguide discontinuity problems. The choice of parameters of anisotropic PML has been investigated. Using the boundary truncating technique, the solution process of Finite-Element Method (FEM) has been greatly simplified compared with other hybrid methods. The required computational resources have also significantly declined since the anisotropic PML interface can be placed much closer to the scatterer compared to other well known artificial boundary.
文摘Several technical problems of numerical method in TLM procedures arediscussed.The bandwidth of single mode in four kinds of dielectric slab loaded rect-angular waveguides is investigated,and the optimum bandwidth which is related tothe dimensions and dielectric constants is obtained.These results are useful to the de-sign of dielectric slab loaded rectangular waveguide.
文摘The equivalent filter modeling of a rectangular dielectric post in a rectangular waveguide is obtained through the variational expression of input impedance. The reflection coefficient expressed in components of network is in good agreement with the results given by K. Siakavara, et al. (1991), The method can be applied to design filter.
文摘The guided and leaky modes of a planar dielectric waveguide are eigensolutions of a singular Sturm-Liouville problem. The modes are the roots of a characteristicfunction which can be found with several methods that have been introduced in thepast. However, the evaluation of the characteristic function suffers from numericalinstabilities, and hence it is often difficult to find all modes in a given range. Here anew variational formulation is introduced, which, after discretization, leads either to aquadratic or a quartic eigenvalue problem. The modes can be computed with standardsoftware for polynomial eigenproblems. Numerical examples show that the method isnumerically stable and guarantees a complete set of solutions.
文摘From the mode-marching method,by doing some transforms and derivations,the scatteringand propagation integral equations for solving the problems of discontinuous dielectric structure are ob-tained.The necessary and sufficient condition for the existence of solution of propagating equations is giv-en.It is really the dispersion equation of the dielectric structure.As an example,a succinct solution ofone-step discontinuous dielectric structure is derived.
文摘We study the WKB dispersion equation in non-uniform optical waveguide.There are three methods given in this paper:(1) method of Airy function;(2)method of connection formula;and(3) method of phase shift.At last we make some remarks.
文摘A glass based slab waveguide, coated with a thin patterned high dielectric overlay, is configured into a refractive index sensor. The asymmetric nature of the waveguide configuration is exploited by keeping the mode in the slab waveguide while enhancing the field level in the overlay-superstrate. The sensor's response is examined using the FDTD simulation technique. A sensitivity of up to one part in 105 in the index of refraction discrimination is determined. The nature of the sensor ensures optical fibre compatibility, requires sub-μL sample volumes and provides a high resolution.
