Orthogonality in multibeam antennas is revisited. The difference between orthogonal
beamforming and zero-forced beamforming is highlighted. The intriguing relation between …

The design procedure and measured results of a novel Butler matrix are presented in this
paper. This asymmetrical structure provides fairly flexible phase outputs; therefore, the array …

A multibeam beam-forming network (BFN) for generating 2-D multibeam array antenna
(MAA) is proposed using single-layer substrate integrated waveguide (SIW) technology …

This article proposes a new design approach for filtering crossovers featuring wide-
stopband and dual-band characteristics based on mixed substrate integrated waveguide …

In this article, a new structure for balanced directional couplers (BDCs) in single-layer
technology is presented for the first time. An innovative combination of single-section …

A novel substrate-integrated waveguide (SIW) filtering crossover based on 3-D assembly is
proposed, for the first time. The degenerate orthogonality of the TE102 mode and TE201 …

We propose a new method to design crossovers by employing an embedded homogeneous
cylindrical lens (HCL). Compared with traditional crossover designs, this strategy introduces …

This article presents, for the first time, low-loss small microvias in build-up layers for the next-
generation highdensity high-performance fifth-generation (5G) millimeter-wave (mm-wave) …

In this article, we propose a software–hardware system to improve the quality of image
recovery in millimeter-wave (MMW) imaging systems, which aims to benefit from …

Traditional two-dimensional (2-D) beamforming network (BFN) topology is constructed by
cross-connecting two stacks of one-dimension (1-D) BFNs, which results in a nonplanar …