S. Germain

Bio: S. Germain is an academic researcher from École Normale Supérieure. The author has contributed to research in topics: Microstrip & Power dividers and directional couplers. The author has an hindex of 1, co-authored 1 publications receiving 180 citations.

Development of substrate integrated waveguide power dividers

Abstract: Two classes of substrate integrated waveguide (SIW) power divider are presented, namely, Y- and T-types. Using arrays of via, the SIW power dividers and microstrip transitions are integrated on the same substrate. Design models are presented respectively for the Y- and T-junctions. Experimental results over the Ka band are given for both structures. The Y-junction shows a bandwidth of 25.2% at -18.5 dB while the T-junction shows a bandwidth of 10.2% at -19.0 dB.

The substrate integrated circuits - a new concept for high-frequency electronics and optoelectronics

Abstract: A new generation of high-frequency integrated circuits is presented, which is called substrate integrated circuits (SICs). Current state-of-the-art of circuit design and implementation platforms based on this new concept are reviewed and discussed in detail. Different possibilities and numerous advantages of the SICs are shown for microwave, millimeter-wave and optoelectronics applications. Practical examples are illustrated with theoretical and experimental results for substrate integrated waveguide (SIW), substrate integrated slab waveguide (SISW) and substrate integrated nonradiating dielectric (SINRD) guide circuits. Future research and development trends are also discussed with reference to low-cost innovative design of millimeter-wave and optoelectronic integrated circuits.

Air-Filled Substrate Integrated Waveguide for Low-Loss and High Power-Handling Millimeter-Wave Substrate Integrated Circuits

Abstract: An air-filled substrate integrated waveguide (SIW) made of a multilayer printed circuit board process is proposed in this paper. It is of particular interest for millimeter-wave applications that generally require low cost and low-loss performance and excellent power-handling capability. This three-layered air-filled SIW allows for substantial loss reduction and power-handling capability enhancement. The top and bottom layers may make use of a low-cost standard substrate such as FR-4 on which baseband or digital circuits can be implemented so to obtain a very compact, high-performance, low-cost, and self-packaged millimeter-wave integrated system. Over Ka-band (U-band), it is shown that the air-filled SIW compared to its dielectric-filled counterparts based on Rogers substrates RT/Duroid 5880 and also 6002 reduces losses by a mean value of 0.068 dB/cm (0.098 dB/cm) and 0.104 dB/cm (0.152 dB/cm), increases average power-handling capability by 8 dB (6 dB) and 7.5 dB (5.7 dB), and quality factor by 2.7 (2.8) and 3.6 (3.8) times, respectively. The peak power-handling capability of the proposed structure is also studied. A wideband transition is presented to facilitate interconnects of the proposed air-filled SIW with dielectric-filled SIW. Design steps of this transition are detailed and its bandwidth limitation due to fabrication tolerances is theoretically examined and established. For validation purposes, a back-to-back transition operating over the Ka-band is fabricated. It achieves a return loss of better than 15 dB and an insertion loss of ${\hbox{0.6}} \pm {\hbox{0.2 dB}}$ ( ${\hbox{0.3}} \pm {\hbox{0.1}}~{\hbox{dB}}$ for the transition) from 27 to 40 GHz. Finally, two elementary circuits, namely, the T-junction and 90 $^{\circ}$ hybrid coupler based on the air-filled SIW, are also demonstrated.

Compact super-wide bandpass substrate integrated waveguide (SIW) filters

Abstract: It is known that the substrate integrated waveguide (SIW) features high-pass characteristics of the conventional waveguide, and a periodic structure (PS) generally presents bandstop characteristics. Therefore, a super-wide-band bandpass characteristic should be realized by combining some sort of PS into the SIW. In this paper, three types of compact SIW-PS wide-band bandpass filters are proposed and investigated with simulation and experiment. Performances of a super-wide bandpass, for instance, 8.5-16.5 GHz in this case study, with low insertion loss and sharp out-of-band characteristics are observed from both simulated and measured results.

Multilayered substrate integrated waveguide (MSIW) elliptic filter

Abstract: This letter presents the design and experiment of a novel elliptic filter based on the multilayered substrate integrated waveguide (MSIW) technique. A C-band elliptic filter with four folded MSIW cavities is simulated by using high frequency structure simulator software and fabricated with a two-layer printed circuit board process, the measured results show good performance and in agreement with the simulated results.

A new six-port junction based on substrate integrated waveguide technology

Abstract: A six-port junction based on the substrate integrated waveguide (SIW) technology is proposed and presented. In this design of such a junction, the SIW is first converted to an equivalent rectangular waveguide, then regular rectangular waveguide design techniques are used. In this structure, an SIW power divider and SIW hybrid 3-dB coupler are designed as fundamental building blocks. A six-port junction circuit operating at 24 GHz is fabricated and measured. Good agreement between simulated and measured results is found for the proposed six-port junction.