Serge Vigneron

Improvement of Global Performances of Band-Pass Filters using Non-Conventionnal Stepped Impedance Resonators

In this paper, we propose the use of non-conventionnal stepped impedance resonators to built high performance band-pass filters. Particularly, we show that it is possible to improve the control of spurious responses outside of a selected bandwidth over a very large frequency range. New specific synthesis methods are developed to design such filters. Practical investigations are carried out in order to validate the method Furthermore, the proposed method is potentially attractive in various domains, like future multi-standard mobile systems (GSM/DECT) or millimeterwave local communication systems.

A two zero fourth order microwave waveguide filter using a simple rectangular quadruple-mode cavity

In order to reduce the size of microwave waveguide filters, triple and quadruple mode filters in circular waveguide have been investigated intensively. However, the research for such filters in rectangular waveguide is still poor and the rare trials have led to complicated sensible structures with loaded cavities. This paper describes a fourth order filter with two transmission zeroes obtained with only one basic rectangular cavity and two irises. Neither coupling nor tuning screws are needed. The analysis at the discontinuities is performed by the moment method. The synthesis lies on an optimization method based on the genetic algorithm.

Design and realization of a four pole elliptic microwave filter using low dielectric loaded cavities

The aim to increase the electrical properties of high power narrow band width filters required for space applications leads us to propose an alternative to classical circular metallic cavities. The introduction of dielectric media in metallic cavities permits to obtain high unloaded quality factor in devices of reduced sizes. An experimental four pole dual mode elliptic filter is constructed using these resonators. The test results are in excellent agreement with the filtering objective.

A new dielectric loaded cavity for high power microwave filtering

This paper is devoted to high electrical performance filter realization for space application. A new form of new dielectric plate resonator shielded in a metallic cavity is presented. It is suitable for high power applications and presents the advantage to be easily manufactured. The finite element method is applied to design the resonators. Experimental 4 pole quasi elliptic filters have been realized to prove the efficiency of our new technique.

A simple design procedure for microstrip resonator filters with a single pair of transmission zeros

Current microwave communication systems need high-performance narrow-band bandpass filters of size who is compatible with devices including MIC or MMIC components. These needs are expressed especially in communication satellites where payload dimensions and weights are important criteria. Multiple coupled resonator filters are good candidates in this respect. Thanks to their ability to place transmission zeros near cut-off frequencies, high selectivity with a restricted number of resonators is obtained. This characteristic is of great interest in the case of narrow-band filters where losses are strongly related to the number of resonators. Nevertheless, making these filters with coupled microstrip resonators presents several difficulties due to the technology. In fact, the discontinuities presented in this topology and the velocity phase differences on parallel coupled lines make the synthesis of this kind of filter tedious. With the aim of answering this problem, a complete design procedure is presented in this paper which allows this kind of filter to be designed easily on any commercial microwave circuit simulator software. In order to validate particular elements incorporated in the procedure, a four order X-band filter was designed. This filter is intended to be inserted in a small size satellite transponder.

New miniaturized dielectric loaded cavity microwave resonators

Two original dielectric resonator topologies are presented: the first one is proposed to reduce the resonator sizes and the second to increase the resonator Q0 for power applications.

Inter-Cavity Iris Design for Five-Pole in Line Elliptic Filter

The design of a five-pole in line elliptic filter using TEl13 and TM012 modes presented. Simultaneous TE/TE and TE/TM mode coupling between the dual and the triple mode cavities is provided by a single displaced rectangular iris. In the present work, the modelling of the discontinuities is based on a variational integral multimodal method. This rigorous and accurate method allows to determine the optimum iris dimensions and position which ensure both required couplings. The response of a designed filter (central frequency 10 GHz and bandwidth 40 MHz) will be presented.

A Ku-band MMIC Transversal Band-Pass Active Filter

Monolithic transversal and recursive microwave active filters overcome the, drawback of heavy resonant elements and lack of operational amplifiers in high frequencies domain. We present a GaAs transversal MMIC filter centred at 11.7 GHz. The experimental results show great possibilities for future-agile pre-filtering modules in new generations of telecommunications receivers. The GaAs MMIC transversal active filter presented in this paper combinies pseudo-elliptic filters performances with a polynomial structure. The fundamental points of our work are: - easy-to-time effective synthesis technique with a new dedicated program for circuit calculations - stability of the circuit ensured by a simple construction and a good reproducibility - original idea of using lumped elements in telecommunications frequencies domain which allows a direct application of the theory - demonstration of the agile nature of these filters.

L-Band Power Dielectric Resonators Filters for Space Applications

In order to minimize the mass and the volume of the equipments of satellites payloads, a high power bandpass filter using square cross dielectric resonators excited on the TM110 mode has been developped and tuned. The resonator has a high unloaded quality factor, measured to 6500 and its construction provides a sufficient thermal diffusion path to the metal housing.