Open Access
Generation of the HE11 mode from monomode smooth circular waveguide
(1996) Gonzalo García, Ramón; Río Bocio, Carlos del; Sorolla Ayza, Mario; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
In this paper, we present an original taper design to obtain the HE11 corrugated circular waveguide mode exciting with a pure TE11 monomode smooth circular waveguide mode. The proposed corrugated taper has a longitudinal section composed of two hyperbolic profiles in series, one concave and the other convex united at a point, such that the derivative is continuous. Superimposed there is an additional tapering of the corrugation depth that goes from l/2 at taper input to l/4 within the first hyperbola. This original synthesis procedure has been successfully tested by computational simulation. The calculation method has been validated be experimental results of other authors.
Open Access
Very short and efficient feeder design from monomode waveguide
(IEEE, 1997) Gonzalo García, Ramón; Teniente Vallinas, Jorge; Río Bocio, Carlos del; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
In this paper, we present an original and short corrugated horn antenna profile to obtain the HE11 corrugated circular waveguide mode exciting with a pure TE11 monomode smooth circular waveguide mode. We will obtain a far field pattern with a very low crosspolarization, high symmetry and very low sidelobes in a wide frequency band. The proposed corrugated antenna has a longitudinal section composed of two hyperbolic profiles in series, one concave and the other convex united at a point, such that the derivative is continuous. Superimposed there is an additional tapering of the corrugation depth that goes from λ/2 at taper input to λ/4 within the first hyperbola. This original synthesis procedure has been successfully tested by computational simulation. The calculation method has been validated with experimental results of other authors.
Open Access
Antenas de bocina optimizadas para acoplar modos gaussianos de orden superior
(1995) Río Bocio, Carlos del; Gonzalo García, Ramón; Sorolla Ayza, Mario; Thumm, Manfred; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
The concept of higher order free space modes, gaussian-like beam modes can be applied to efficiently transport the power generated by a gyrotron for technological applications. Waveguide modes can be coupled properly to higher order gaussian modes. These modes can be guided by an optimized higher order beam waveguide to the final experiment. A family of optimized non linear horn antennas is investigated in order to maximize the coupling between the guided output modes of a technological gyrotron and the free space modes. The numerical computations show very favourable coupling to higher order gaussian modes, with a conversion effiencies of about 99.8%.
Open Access
Gaussian profiled horn antennas
(1999) Gonzalo García, Ramón; Teniente Vallinas, Jorge; Río Bocio, Carlos del; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
In many different applications parameters such efficiency, gain, directivity, etc., are really critical. By using the Gaussian techniques presented here, the radiating features of existing horn antenna systems can be improved, only by adding some portion of Gaussian horn antenna at the end or designing a new horn antenna system. In this paper some special features of the Gaussian profiled horn antennas are presented. Furthermore, different design methods based on the Gaussian techniques are analyzed, describing the advantages of these methods versus the existing methods. Some practical examples, comparisons and measurements are also given.
Open Access
SCATTMAT: a mode matching and generalized scattering matrix code for personal computers in a windows environment
(1997) Liberal, Antonio; Río Bocio, Carlos del; Gonzalo García, Ramón; Sorolla Ayza, Mario; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
In this paper, a computer aided design tool is presented to simulate symmetrical radially deformed circular waveguide microwave components. This tool works with the well-known “Mode Matching and Scattering Matrix” techniques, and it has been developed in C++ language in a Windows environment, to obtain the most friendly interface between the user and the code. The most important feature of the presented code is that it includes the possibility to display the internal mode power evolution along the component. The code has been successfully validated with numerical and experimental results from different authors.
Open Access
Generation of the HE11 mode in rectangular waveguide using gaussian techniques
(IEEE, 1999) Teniente Vallinas, Jorge; Gonzalo García, Ramón; Sorolla Ayza, Mario; Río Bocio, Carlos del; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
A new and efficient design of a rectangular corrugated waveguide mode converter, from TE10 mode in a smooth rectangular monomode waveguide to HE11 mode in a corrugated rectangular waveguide, is proposed. The main idea is the application of Gaussian design techniques, described in the given references, previously applied in circular waveguides. By using these techniques compact and very efficient components are obtained. The obtained far field pattern is rather good as illuminator of square or rectangular parabolic reflectors, with very low sidelobes and crosspolarisation levels, avoiding the use of a rectangular to circular waveguide converter. Simulations by using the HP’s Finite Element code HFSS shown very promising results.
Open Access
Paraxiality considerations of higher order gaussian modes
(1996) Río Bocio, Carlos del; Gonzalo García, Ramón; Sorolla Ayza, Mario; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
Frequently, gaussian modes are used as free space wave equation solutions. This is not true since they are obtained assuming certain paraxial character in them. In this paper, we present an original study of the condition for paraxiality of higher order gaussian modes solutions of the wave equations in free space. A bound for the product of number (k) in free space and the beam waist of a family of modes is obtained, in terms of the mode indexes - the bound being more restrictive the larger the order of the mode.
Open Access
Alimentadores gaussianos en guía de onda rectangular
(1999) Teniente Vallinas, Jorge; Gonzalo García, Ramón; Río Bocio, Carlos del; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
A new and efficient design of a rectangular corrugated waveguide mode converter, from TE10 mode in a smooth rectangular monomode waveguide to HE11 mode in a corrugated rectangular waveguide, is proposed. The main idea is the application of Gaussian design techniques, described in the given references, previously applied in circular waveguides. By using these techniques compact and very efficient components are obtained. The obtained far field pattern is rather good as illuminator of square or rectangular parabolic reflectors, with very low sidelobes and crosspolarisation levels, avoiding the use of a rectangular to circular waveguide converter.
Open Access
Generación del modo HE11 a partir de una guía circular lisa monomodo
(1996) Gonzalo García, Ramón; Río Bocio, Carlos del; Teniente Vallinas, Jorge; Sorolla Ayza, Mario; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
In this paper, we present an original taper design to obtain the HE11 corrugated circular waveguide mode exciting with a pure TE11 monomode smooth circular waveguide mode. The proposed corrugated taper has a longitudinal section composed of two hyperbolic profiles in series, one concave and the other convex united at a point, such that the derivative is continuous. Superimposed there is an additional tapering of the corrugation depth that goes from l/2 at taper input to l/4 within the first hyperbola. This original synthesis procedure has been successfully tested by computational simulation. The calculation method has been validated by experimental results of other authors.
Open Access
Optimum horn antennas for high order mode beam waveguides
(1995) Río Bocio, Carlos del; Gonzalo García, Ramón; Sorolla Ayza, Mario; Thumm, Manfred; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
Higher order free space modes can be considered as serious candidates for power millimeter wave transmission in advanced material processing by using medium power CW gyrotrons. These modes can be propagated in a beam waveguide with properly designed mirrors. Here, we present some optimal ways to excite these higher order free space modes from circular symmetric cylindrical waveguide modes by using optimal non linear horn launchers. An original synthesis procedure is proposed which has been successfully tested by computational simulation.