In this work we present the design and fabrication in metallic 3D-printing of a compact conformal slotted waveguide antenna array operating in the Ku-band. The application objective, although not limited only to this, is the optimisation of an antenna element which by stacking will be able to form a quasi-cylindrical sector. A beamforming network will be used for beam-steering in the elevation plane as coverage in the azimuthal plane is guaranteed by the conformal geometry. The compact design of the antenna element is therefore of great significance. For this reason, a direct feeding scheme by a coaxial connector is adopted. The antenna has been optimized following multiple parametric analyses of its geometrical parameters for the enhancement of the bandwidth, return losses and realized gain. The antenna was fabricated with Selective Laser Melting in aluminium and the experimental results agree well with the numerically calculated ones. The proposed CSWAA exhibits a reflection coefficient below -10 dB, realized gain above 14 dBi, as well as good cross-polarization and side-lobe level over a relative bandwidth of 8%.

This article presents the implementation of the intrachip propagation channel in the case of a wireless interconnect network-on-chip used for parallel computing applications. These wireless interconnects still require precise propagation models to demonstrate that they can be considered as a realistic efficient alternative to the wired interconnects. First, we show the advantages of wireless solutions for broadcast applications. As this type of circuit will be realized using silicon as the main component, we present in the literature review the problems and constraints of integrated antennas and channels on silicon. Then, a deep electromagnetic study for the intrachip transmission is conducted, with measurements done using two manufactured prototypes of printed dipole antennas on silicon in the Ka-band (26-40 GHz) and in the V-band (40-75 GHz) with different scenarios. The good agreement between simulations and measurements validates the problems encountered due to the silicon substrate and its environment. Finally, we propose perspective solutions in order to improve the intrachip transmission on integrated circuits and to prove the feasibility of the wireless network on chip using integrated antennas.

This paper, which concerns the wireless network concept, presents the characterization and demonstration of silicon propagation channel control performed at around 60 GHz. The aim is to optimize the propagation channel in order to transmit signal in a large frequency band, this for broadcast internal Networks-on-Chip communication application. First, slot antennas in the frequency band [30-67 GHz] directly integrated on high resistivity silicon (HR-Si) surrounded by low-resistivity silicon (LR-Si) were designed and measured. The transmission and matching parameters are presented for inter-element spacings of 6 mm and 14 mm and demonstrate the interest of controlling the propagation channel by using absorbent boundaries from a controllable bias voltage. The results are also compared with the existing literature and show large 3 dB bandwidths. The S-parameters of the measured slot antennas are then integrated and simulated in the time domain using on-off keying (OOK) modulation, making it possible to evaluate the maximum throughput and bit-energy efficiency.

A dual-band slotted waveguide array (SWA) antenna is designed using a single waveguide by placing the radiating slots for 18 GHz and 24 GHz on the same antenna aperture. These bands are excited using a single excitation point through a conventional waveguide feeding technique to radiate unidirectional radiation patterns of same polarization. Theoretical analyses are carried out to study the conductance of the slots to understand their effects on the dual-band performance. Numerical analyses are performed to optimize the antenna by considering mutual coupling. The antenna is fabricated using stereolithography (SLA) and direct metal laser sintering (DMLS) processes to compare its performance in different additive manufacturing techniques. In characterizing the fabricated prototype, an impedance matching of | S ₁₁ | < −10 dB and the boresight antenna gains of 14 dBi and 17.4 dBi are measured in these bands with unidirectional and linearly polarized radiation patterns. A quantitative comparison among dual-band SWA antennas is presented at the end of the manuscript to highlight the uniqueness of the proposed approach over the state-of-the-art solutions.

The recent developments in electronic cards such as the network equipment are characterized by the miniaturization of the board size and the increasing complexity of the layout. Because of these requirements, multi-layered printed circuit boards are commonly used and vias connecting signal lines on different layers, or integrated circuit devices to power and ground planes, are frequently used and often essential. However, a via is not an ideal transmission line. Besides, it creates discontinuities at high frequencies leading to high insertion loss degradation of signal which limits the performances of integrated circuit and systems. In this paper, the impacts of coupling between via and parallel-plates cavity on the response of microwave integrated devices are highlighted in the first part. Then, to describe the intrinsic interaction between the via transition and parallel-plate modes, the notion of parallel-plates matrix impedances is presented and new boundary conditions like open or plated through holes shielded boundaries of the cavities are introduced. Then, using this physics-based model, an intuitive equivalent circuit has been developed. Finally, the proposed approach and the equivalent circuits were validated by using comparisons with electromagnetic simulations and measurements in different scenarios.