A dual-layer 3-dB substrate-integrated waveguide power divider/combiner is designed, fabricated, and tested. Very good input and output matching as well as high isolation are exhibited over a ...measured 50% fractional bandwidth when a 10-dB reference level is considered. A completely shielded design significantly reduces insertion losses when compared to the majority of other state-of-the-art architectures. This device can be integrated with multilayer planar circuits, and it is fully compatible with the standard printed-circuit board technology.
A new modeling approach for the design of planar multilayered meander-line polarizers is presented. For the first time a multielement equivalent circuit is adopted to characterize the meander-line ...unit cell. This equivalent circuit significantly improves the bandwidth performance with respect to the state-of-the-art. In addition to this, a polynomial interpolation matrix approach is employed to take into account the dependence on the meander-line geometrical parameters. This leads to an accuracy comparable to that of a full-wave analysis. At the same time, the computational cost is minimized so as to make this model suitable for real-time tuning and fast optimizations. A four-layer polarizer is designed to validate the presented modeling procedure. Comparison with full-wave simulations confirms its high accuracy over a wide frequency range.
An X-band H-plane groove gap waveguide magic-T is presented as a combination of an H-plane and an E-plane T-junction. Two architectures can be derived by orientating the sum and difference ports to ...the same or opposite directions, respectively. Slot coupling allows the reduction of the device dimensions along the E-plane, and such a low profile can be attractive in all groove gap waveguide applications where compactness is required. A proof-of-concept prototype is fabricated with standard low-cost CNC milling machine manufacturing techniques. Good agreement between simulations and measurements is observed.
A coaxial-to-groove gap waveguide transition is proposed for the first time, addressing the lack of similar designs in the state-of-the-art literature. An in-line configuration is adopted in case of ...stringent space requirements in groove gap waveguide systems. This device has no dielectric and makes use of a waveguide multi-step ridged section connected to the inner conductor of a coaxial line. Three versions are presented, covering progressively wider bandwidths depending on the number of employed steps. The three configurations achieve 20-dB return loss fractional bandwidths of 2.63%, 16.79%, and 38.08%, and 30-dB return loss fractional bandwidths of 0.84%, 10.63%, and 33.49%, with a simulated insertion loss always better than 0.05 dB when a realistic metal conductivity of 2 × 10 7 S/m is assumed. A tolerance analysis on the most critical geometrical parameters is provided to assess the mechanical feasibility, preserving a remarkable performance at X band.
An original architecture to generate two orthogonal circular polarizations with slotted waveguide arrays is presented in this communication. The proposed solution consists of two interleaved slotted ...ridge waveguide arrays sharing the same aperture and feeding a common polarizing layer represented by a dual circular polarization horn array. The radiating element realizing the linear‐to‐circular polarization conversion is made of a slot‐fed compact septum polarizer flaring into a pyramidal horn. The horn‐loaded slot model is extracted, thus allowing the synthesis of large arrays. A dual circular polarization slot‐fed horn array antenna is designed for Ku‐band operation. The two polarizations, when combined with proper phase relation, enable the tracking of two orthogonal linear polarizations. The antenna exhibits remarkable performance for both circular and linear polarization operating modes.
In this work, the issue of limited bandwidth typical of microstrip antennas realized on a single thin substrate is addressed. A simple yet effective design approach is proposed based on the ...combination of traditional single-resonance patch geometries. Two novel shaped microstrip patch antenna elements with an inset feed are presented. Despite being printed on a single-layer substrate with reduced thickness, both radiators are characterized by a broadband behavior. The antennas are prototyped with a low-cost and fast manufacturing process, and measured results validate the simulations. State-of-the-art performance is obtained when compared to the existing literature, with measured fractional bandwidths of 3.71% and 6.12% around 10 GHz on a 0.508-mm-thick Teflon-based substrate. The small feeding line width could be an appealing feature whenever such radiating elements are to be used in array configurations.
This communication presents an innovative dualpolarization antenna working at Ku band (14 ÷ 14.5 GHz) based on slotted waveguide array (SWGA) technology. The proposed solution allows to ...simultaneously generate two orthogonal circular polarizations that are combined to generate two orthogonal linear polarizations with polarization-tracking capabilities and very low cross-polarization level thanks to the symmetry of the structure. The antenna is composed of two interleaved slotted ridge waveguide arrays connected to a polarizer, realized with an array of triangular-base ridged cavities. Slots, located at the waveguide centerline, are excited by means of posts avoiding offsets and leading to a regular grid arrangement. Radiating elements are placed in a triangular lattice to minimize the azimuth sidelobe level and provide high EIRP levels.
An original in‐line coaxial‐to‐rectangular waveguide transition including stepped ridged sections is presented. This device differs from the state of the art because of the coaxial inner conductor ...not being in electrical contact with the ridge, leading to considerable mechanical advantages. In addition to this, capacitive coupling can extend the bandwidth even with a few matching sections when compared with the traditional counterpart presenting DC contact with the first ridge. An ultra‐compact transition is designed, manufactured, and tested in back‐to‐back configuration. From measured data, a return loss better than 20 dB on a bandwidth of 1.27 GHz (12.2%) is observed in this configuration. An average insertion loss of 0.11 dB can be derived for the standalone transition.
An X‐band compact and low‐profile waveguide magic‐T Vincenti Gatti, Roberto; Rossi, Riccardo; Dionigi, Marco ...
International journal of RF and microwave computer-aided engineering,
September 2019, Letnik:
29, Številka:
9
Journal Article
Recenzirano
Odprti dostop
An X‐band low‐profile waveguide magic‐T is presented as a combination of two compact and co‐planar E‐plane and H‐plane T‐junctions. Two architectures are proposed according to the sum and difference ...ports lying on the same side or on opposite sides. This can be an attractive feature in the design of compact architectures. A proof of concept is manufactured with low‐cost 3D printing technology and electroplated. Good agreement between simulated and measured results is observed.
A low-profile single-ridge waveguide magic-T is proposed as a combination of two T-junctions at an X band. A slot coupling technique is used to reduce the component dimensions in the E-plane, thus ...leading to a low profile. The device can assume two configurations by arranging the sum and difference ports in the same or opposite direction, an attractive feature in the design of beamforming networks with complex routing. A magic-T prototype is fabricated using laser powder bed fusion additive manufacturing techniques. Good agreement between simulations and measurements is found.
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