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Author

Giorgio Bertin

Other affiliations: CSELT
Bio: Giorgio Bertin is an academic researcher from Telecom Italia. The author has contributed to research in topics: Resonator & Q factor. The author has an hindex of 13, co-authored 52 publications receiving 533 citations. Previous affiliations of Giorgio Bertin include CSELT.


Papers
More filters
Journal ArticleDOI
TL;DR: In this article, a cavity resonator with elliptical cross section is proposed to realize dual-mode narrow-band filters without tuning and coupling elements, which significantly enhances the unloaded Q, the ability to operate with higher power levels, and the ease of manufacturing.
Abstract: A novel cavity resonator with elliptical cross section is proposed in order to realize dual-mode narrow-band filters without tuning and coupling elements. The absence of any discontinuity inside the cavities significantly enhances the unloaded Q, the ability to operate with higher power levels, and the ease of manufacturing. Proper choice of the ellipticity and of the inclination angle controls the desired coupling and tuning actions. Dual-mode coupling is generated by the step discontinuity between the input rectangular waveguide and an inclined elliptical waveguide. A rigorous full-wave electromagnetic model for this discontinuity has been developed and validated using a specialized hardware configuration. Experimental data compare very favorably with theoretical results. Representative prototypes of elliptical cavities exhibiting various degrees of coupling have been carefully measured proving the accuracy of the model and its applicability for narrow-band X- and Ku-band filter design. The full-wave analysis of a complete four-pole narrow-band elliptic filter at 12 GHz and the measured response of a corresponding prototype demonstrate the capability of achieving reliable results using the proposed approach.

73 citations

Journal ArticleDOI
TL;DR: In this article, the design and optimization of a new polarizer structure realized in circular waveguide with insertion of elliptical irises is described, showing a considerable reduction in size and weight when compared to previously known realizations.
Abstract: We describe the design and optimization of a new polarizer structure realized in circular waveguide with insertion of elliptical irises. The device is compact, showing a considerable reduction in size and weight when compared to previously known realizations. It requires manufacturing by milling techniques only and, since it is composed entirely by waveguides with separable cross sections, it is also well suited for electromagnetic modeling. Measured and theoretical results for a polarizer with a 90/spl deg//spl plusmn/1/spl deg/ differential phase shift and a return loss better than 35 dB for both polarizations over the operating frequency band confirm the validity of the proposed design.

67 citations

Journal ArticleDOI
TL;DR: In this article, a hybrid computer-aided design technique, which employs the standard generalized scattering matrix description and a new method, based on the three-dimensional generalized admittance matrix representation, for the efficient and reliable analysis of compact ortho-mode transducers (OMT).
Abstract: We describe a hybrid computer-aided-design technique, which employs the standard generalized scattering matrix description and a new method, based on the three-dimensional generalized admittance matrix representation, for the efficient and reliable analysis of compact ortho-mode transducers (OMT). A rigorous investigation of the numerical convergence properties of the electromagnetic simulators is carried out by using as a benchmark the measurements of a specifically built structure. The electromagnetic simulators are used for the efficient computer-aided optimization of the OMT and a procedure for the dynamical optimization of such components is introduced and tested by designing several OMT's operating at L, S, and Ku frequency bands. The component design, entirely carried out at computer level, has demonstrated significant advantages in terms of development times and no need of post-manufacturing adjustments. The very satisfactory agreement between experimental and theoretical results further confirms the validity of the proposed technique.

62 citations

Journal ArticleDOI
TL;DR: In this paper, a four-pole dual-mode elliptic filter is realized in circular cavity without screws by using a novel arrangement consisting in the insertion of a short section of inclined rectangular waveguide in the middle of the cavity body.
Abstract: A four-pole dual mode elliptic filter is realized in circular cavity without screws. The desired coupling and tuning actions are achieved by using a novel arrangement consisting in the insertion of a short section of inclined rectangular waveguide in the middle of the cavity body. In this way we realize dual-mode filters by using only junctions of waveguides with rectangular and circular cross sections, thus enabling a very efficient CAD of such filters. This arrangement also proves particularly convenient from the manufacturing viewpoint. Measured response of a breadboard channel filter operating at Ku-Band shows good agreement with theoretical simulations; a sensitivity analysis confirms the validity of the proposed design.

59 citations

Proceedings ArticleDOI
01 Oct 1999
TL;DR: In this paper, a computer-aided optimization technique for the efficient and reliable design of compact wide-band waveguide septum polarizers (WSP) is described.
Abstract: We describe a computer-aided optimization technique for the efficient and reliable design of compact wide-band waveguide septum polarizers (WSP). Wide-band performance is obtained by a global optimization which considers not only the septum section but also several step discontinuities placed before the ridge-to-rectangular bifurcation and the square-to-circular discontinuity. The proposed technique mnakes use of a dynamical optimization procedure which has been tested by designing several WSP operating in different frequency bands. In this work two examples are reported, one operating at Ku band and a very wideband prototype (3.4-4.2 GHz) operating in the C band. The component design, entirely carried out at computer level, has demonstrated significant advantages in terms of development times and no need of post manufacturing adjustments. The very satisfactory agreement between experimental and theoretical results further confirm the validity of the proposed technique.

25 citations


Cited by
More filters
Patent
31 Jul 2013
TL;DR: In this paper, the authors present a system for the registration and management of active grid elements, where grid elements are transformed into active grid element following initial registration of each grid element with the system, preferably through network-based communication between grid elements and a coordinator, either in coordination with or outside of an IP-based communications network router.
Abstract: Systems, methods, and apparatus embodiments for electric power grid and network registration and management of active grid elements. Grid elements are transformed into active grid elements following initial registration of each grid element with the system, preferably through network-based communication between the grid elements and a coordinator, either in coordination with or outside of an IP-based communications network router. A multiplicity of active grid elements function in the grid for supply capacity, supply and/or load curtailment as supply or capacity. Also preferably, messaging is managed through a network by a Coordinator using IP messaging for communication with the grid elements, with the energy management system (EMS), and with the utilities, market participants, and/or grid operators.

278 citations

01 Jan 1943

265 citations

Journal ArticleDOI
TL;DR: In this paper, the authors proposed a new concept of narrow bandpass filters leading to perfectly controlled electrical responses within both the required operating bandwidth and adjacent undesired bands, and a specific topology is considered for such a "global synthesis": in comparison with conventional filter performances, it provides significant improvements in terms of rejection control.
Abstract: This paper reports on a new concept of narrow bandpass filters leading to perfectly controlled electrical responses within both the required operating bandwidth and adjacent undesired bands. A specific topology is considered for such a "global synthesis": in comparison with conventional filter performances, it provides significant improvements in terms of rejection control. The attenuated frequencies are each located apart from the bandpass frequencies and controlled by means of n transmission zeros introduced through original dual-behavior resonators (DBRs). These resonators are based on the association of different parallel open-ended stubs and allow the designer to independently control the in-band and out-of-band responses of the filter. A global synthesis approach is also discussed on a simplified architecture based on stepped impedance stubs, and the experimental results shown clearly validate the proposed concept. This simplification reduces the number of degrees of freedom when designing a DBR, and consequently the two transmission zeros become dependent.

232 citations

Journal ArticleDOI
TL;DR: In this paper, a planar diplexer based on the complementary response characters of substrate integrated waveguide (SIW) dual-mode filters with circular and elliptic cavities is proposed.
Abstract: A novel high-performance millimeter-wave planar diplexer is developed based on the complementary characters of substrate integrated waveguide (SIW) dual-mode filters with circular and elliptic cavities by making the tradeoff between the isolation, insertion loss, and selectivity. The responses of the dual-mode SIW circular and elliptic cavities are first investigated. It can be found that the upper side response of the circular cavity and the lower side response of the elliptic cavity are very steep. The diplexers with high isolation performance are then designed based on the complementary response characters of circular and elliptic cavities. A diplexer with two dual-mode SIW circular and elliptic cavities is designed and fabricated with a normal printed circuit board process. The measured insertion losses are 1.95 and 2.09 dB in the upper and lower passbands centered at 26 and 25 GHz with the fractional bandwidths of 5.2% and 5.4%. The isolation is lower than - 50dB

205 citations

Journal ArticleDOI
TL;DR: In this article, a new family of dual-mode filters based on the use of simple inductive discontinuities in a rectangular waveguide environment is described. But the proposed filter structure can be analyzed and optimized very efficiently using multimode equivalent network representations, thus leading to a simple and rapid development procedure.
Abstract: In this paper, we describe a new family of dual-mode filters that is based on the use of simple inductive discontinuities in a rectangular waveguide environment. The proposed filter structure can be analyzed and optimized very efficiently using multimode equivalent network representations, thus leading to a simple and rapid development procedure. In addition to theory, the measured performance of a number of filter structures is also presented, thereby fully validating the proposed filter concept.

173 citations