Alexandre Manchec

Synthesis of capacitive-coupled dual-behavior resonator (CCDBR) filters

The two topologies and associated syntheses described here are dedicated to the design of capacitive-coupled dual-behavior resonator filters. The technique is based on the coupling of adjacent dual-behavior resonators (DBRs). The aim is to control the spurious resonances associated to classical DBR filters. In the first coupling technique, the inverter is replaced with an equivalent scheme composed of a set of three capacitors, i.e., a positive capacitor associated with two negative ones in parallel on both sides. The second technique relies on the same principle, but two equivalent schemes are moved along each stub of the resonators; the capacitance is then calculated by considering the position of the coupling effect on the stub and the value of the inverter. In both cases the synthesis is totally defined. In order to validate this concept, capacitive-coupled DBR filters and classical filters were designed on alumina substrate so as to compare simulation and experimental data

Synthesis of dual behavior resonator (DBR) filters with integrated low-pass structures for spurious responses suppression

This paper deals with a rigorous synthesis of dual behavior resonator (DBR) filters with integrated low-pass filter for spurious response suppression. The basic low-pass filter consists in an L-C-L structure associating two transmission lines and an open-ended stub. After full definition, the synthesis is validated from comparisons between simulation- and experimental-data acquired with some third-order filters designed on alumina substrate

Planar tri-band filter based on dual behavior resonator (DBR)

This paper reports on the application of dual behavior resonators to design triband filters. The principle is briefly presented by considering monoband, dual-band and triband filters. A circuit is proposed by using an approximate synthesis. Then, a hybrid (electromagnetic / circuit) simulation is performed to take into account the parasitic effects induced by the junction discontinuities and to allow a fast triband optimization in the same time. An example of layout with associated simulated and experimental results is proposed.

General Synthesis of

This letter deals with a general method and synthesis devoted to the achievement of N-band resonators. The general topology is based on the dual behavior resonator. Indeed, this kind of topology allows the independent control of different transmission zeros and resonances. Thus, the topology proposed in this study consists of a parallel association of N+1 different bandstop structures to get N bandpasses separated by a transmission zero. After introduction of the general synthesis, the principle will be validated by the achievement of a four-band resonator in microstrip technology

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This paper deals with miniaturized and wide band bandpass filter. This filter is based on an original topology based on series and parallel resonators. Series resonators are realized using open-ended coupled lines and parallel resonator is implemented using an open-ended stub. This hybrid topology based on two kinds of stub leads to a twice more compact 5th order design compared to the conventional 5th order approach. Moreover, the use of resonators presenting different periodic behaviors implies additional transmission zeros and so, enhances the rejection of the filter. Liquid crystal polymer (LCP) is chosen by considering its low cost, good and stable RF performance over the frequency of interest and its ability to act both as a substrate and a package to obtain wide band filter. So, the combined use of this technology and this topology leads to a filter that presents very good electrical performances in a reduced occupied area. A compact wideband filter (2.38-4.2 GHz) with insertion loss of 1.2 dB and rejection has been designed by using a full-wave analysis and measurements are presented.

-Band Resonator Based on

This report describes the design of original planar filters and of a diplexer based on dual behavior resonator (DBR) filter, and introduces measurement data. The specifications dealt with a limited frequency band in Ku-band where a high isolation is needed between Rx and Tx frequency bands. This study evidences the benefits of oversized DBR in particular for getting a high rejection level. Moreover, folding the oversized resonators allows one to keep constant the filter overall size. The first DBR filter for the Ku-band receiver is of 3rd-order with a central, folded, oversized and low-frequency stub; the second DBR filter for the Ku-band transmitter is also of 3rd-order with three folded, oversized and high-frequency stubs. Then, a diplexer as presented in Rhodes and Ievy (1979) and Matthanei et al. (1980) was realized from both filters as stated in Goron et al. (2003) and Tudosie and Vahlieck (2004).

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This paper deals with the design of cross-coupled microstrip dual behavior resonator (DBR) filters. It evidences the several ways of cross-coupling DBR filters to get, in particular, either a high level rejection or a flat group delay with a 4th-order filter. The two coupling structures described here are based on the DBR to allow a positive or negative cross-coupling effect. In order to validate this concept three different filters were realized on an alumina substrate. Simulation and experimental data are compared and discussed

-Order Dual Behavior Resonator

This paper presents the development and performance of several dual-band filters for wireless local area network (WLAN) applications. Three dual-band filters meeting the specifications of 802.11 bg (2.412-2.484 GHz) for the lower band and the specifications of 802.11 a-L (5.180-5.320 GHz), 802.11 a-H (5.745-5.805 GHz) and 802.11 a-L&H (5.180-5.805 GHz) for the upper band are presented. These filters are developed based on dual behavior resonator (DBR) topology in combination with a new stepped impedance approach and are implemented for the first time on liquid crystal polymer (LCP) technology. LCP has been chosen because of its low cost, good RF performance and its ability to act both as a substrate and a package. Measurements show a very low insertion loss of -1.25 dB for the lower band and an insertion loss of -2.4 dB and -1.1 dB for the narrow and broad upper bands respectively. This work demonstrates that the proposed design methodology is simple, efficient and allows easy tuning of the filter parameters to suit different specifications.

Wide band, high rejection and miniaturized fifth order bandpass filter on LCP low cost organic substrate

This paper presents a C-band planar filter miniaturized through use of high-permittivity substrates to meet the specifications. The drawbacks associated to such substrates are briefly recalled. To overcome them, the filter under study was based on the DBR topology and realized on a high-K commercial substrate. This ceramic has a relative permittivity of 90 and a low dielectric tangent (tanδ < 10−3). Finally, the results of simulations and measurements are presented and discussed, particularly the footprint reduction.

Ku-band microstrip diplexer based on dual behavior resonator filter

The miniaturization of embarked devices remains a major concern in the space sector. Alternative solutions based on the use of new ceramic materials with very high dielectric permittivity, enhanced electric properties and high temperature stability are worth being investigated. This paper reports on the design of an UHF-microstrip bandpass filter with drastic specifications and based on such a dielectric substrate of relative permittivity εr = 90. Simulation and measurement results highlight some of the possibilities offered by these particular materials.