Jean Philippe Coupez

Accessing to UMTS filtering specifications using new microstrip miniaturized loop-filters

A new topology for the design of microstrip loop-filters is proposed in this paper. This new geometry is used in a coupled-loop-resonator filter in order to improve the out of band rejection (by introducing an additional transmission zero), as well as insertion loss (thanks to a significant circuit size reduction). The design methodology of these filters is first described and then experimental performances are discussed. Finally, a high performance duplexer, specified for UMTS frequencies and requirements (i.e. in the 1.9-2.17 GHz frequency band), is presented. Measured insertion loss is lower than 2.5 dB and an isolation level greater than 40 dB is achieved between Tx/Rx channels, thanks to the multiple out of band transmission zeros introduced in the filter synthesis.

Theoretical and experimental study of various types of compensated dielectric bridges for millimeter-wave coplanar applications

This paper describes a new approach for the integration of dielectric bridges in microwave-integrated-circuit uniplanar technology. Taking into account the electrical influence of these elements on coplanar waveguide, a simple way to compensate these parasitic effects is presented. It consists of locally tuning the dimensions of both the bridges and associated compensation lines. Theoretical and experimental results on coplanar waveguides and T-junctions are given for the millimeter frequency range. Finally, to validate the proposed technique, a bandpass filter including compensated dielectric bridges is implemented.

A new semi-lumped microwave filter structure

A novel narrow-band microwave filter structure is presented. The merit of this circuit lies in the simplicity of design formulas readily applicable to narrow-band filters. The structure can be realized in planar or uniplanar technology. The design formulas yield good results for bandwidths lower than 10%. Bandpass filter with 4% relative bandwidth at 3 GHz was designed with the proposed theory and then implemented in both microstrip and coplanar technologies. Experimental results show good agreement with theoretical predictions.<<ETX>>

Original techniques for designing wideband 3D integrated couplers

In this paper, we propose some original technological configurations for implementing highly coupled wideband structures in a 3D environment. Thanks to a convenient combination of thinkable topologies, difficulties commonly encountered with a classical approach can be solved. Different design examples of couplers are given, and experimental and simulated results are presented.

A novel uniplanar bi-phase (0/spl deg/-180/spl deg/) modulator/mixer

The overall goal of this paper is to design a new modulator/mixer at 38 GHz in uniplanar technology. The primary objective is to develop a theoretical and an experimental study of each elementary block in the millimeter frequency range, allowing us directly to design the device at 38 GHz. As part of this study, a uniplanar modulator/mixer was built in X band in order to aid in the verification of the design concept.The overall goal of this paper is to design a new modulator/mixer at 38 GHz in uniplanar technology. The primary objective is to develop a theoretical and an experimental study of each elementary block in the millimeter frequency range which allows us to design directly the device at 38 GHz. As part of this study, a uniplanar modulator/mixer was built in X-band in order to aid in the verification of the design concept.<<ETX>>

Miniaturized Rx front-end modules for digital beam forming arrays

An original implementation of a receiver for UMTS numerically-controlled smart base-stations is proposed in this paper. A complete analog front-end is inserted within a hybrid-radiating module. The module uses original conformal patches inserted in a machined ground plane. This particular geometry contributes to minimize mutual coupling effects when they are spatially distributed (and thus a better control of the synthesized array); it brings simultaneously a great flexibility for implementing both RF active and passive functions within a common environment, and a significant radiation pattern enhancement. A digital beam-forming platform is proposed and experimentations delivered on different situations.

On the Implementation of Miniaturized and Optimized Transceivers for UMTS Base Stations

An original implementation ofa TX/RX transceiver for future UMTS base stations is proposed in this paper. Machined Foam substrates are stacked at first for implementing a square patch antenna on a composite thick support, then delivering interesting performances in terms of bandwidth and efficiency with respect to planar solutions. Active and passive devices are inserted within a shielded cavity created under the patch, then preventing from size constraints at such frequencies as well as insertion loss and parasitic radiations. A complete experimental procedure is presented for both TX and RX operating modes.