Small Footprint Multilayered Millimeter-Wave Antennas and Feeding Networks for Multi-Dimensional Scanning and High-Density Integrated Systems

This paper overviews the state-of-the-art of substrate integrated waveguide (SIW) techniques in the design and realization of innovative low-cost, low-profile and low-loss (L3) millimeter-wave antenna elements, feeding networks and arrays for various wireless applications. Novel classes of multilayered antenna structures and systems are proposed and studied to exploit the vertical dimension of planar structures to overcome certain limita-tions in standard two-dimensional (2-D) topologies. The developed structures are based on two techniques, namely multi-layer stacked structures and E-plane corners. Differ-ent E-plane structures realised with SIW waveguide are presented, thereby demonstrating the potential of the proposed techniques as in multi-polarization antenna feeding. An array of 128 elements shows low SLL and height gain with just 200g of the total weight. Two versions of 2-D scanning multi-beam are presented, which effectively combine frequency scanning with beam forming networks. Adding the benefits of wide band performance to the multilayer structure, two bi-layer structures are investigated. Different stacked antennas and arrays are demonstrated to optimise the targeted antenna performances in the smallest footprint possible. These structures meet the requirement for developing inexpensive compact millimeter-wave antennas and antenna systems. Different structures and architectures are theoretically and experimentally studied and discussed for specific space- and ground-based appli-cations. Practical issues such as high-density integration and high-volume manufacturability are also addressed

A Review: Substrate Integrated Waveguide Antennas and Arrays

This study aims to provide an overview and deployment of Substrate-Integrated Waveguide (SIW) based antenna and arrays, with different configurations, feeding mechanisms, and performances. Their performance improvement methods, including bandwidth enhancement, size reduction, and gain improvement are also discussed based on available literature. SIW technology, which acts as a bridge between planar and non-planar technology, is a very favorable candidate for the development of components operating at microwave and millimeter wave band. Due to this, SIW antennas and array take the advantages of both classical metallic waveguide, which includes high gain, high power capacity, low cross polarization, and high selectivity, and that of planar antennas which comprises low profile, light weight, low fabrication cost, conformability to planar or bent surfaces, and easy integration with planar circuits

A Combined Electric/Magnetic Field Surface Volume Integral Equation Approach for the Fast Characterization of Microstrip/ Substrate Integrated Waveguide Structures and Antennas

In this contribution, a combined electric field/magnetic field surface/volume integral equation approach is presented with special features for the characterization of substrate integrated waveguide (SIW) components. Due to the use of a parallel-plate waveguide Green’s function, only a small number of volume current basis functions are necessary to model the vias of the SIW sidewalls. The focal point is set on the specification of microstrip-SIW transitions using a via and a pad/antipad configuration for the coupling between the microstrip parts and the SIW and transitions with a two-stage ridged substrate integrated waveguide (SIW) where the SIW has a very thick substrate with regard to the microstrip line making it well suited for the design of a new class of compact end-fire SIW antennas for phased array applications which are partly characterized with CST Microwave Studio. An effective S-parameter extraction is used with both microstrip and special SIW waveguide ports

A comprehensive survey on 'circular polarized antennas' for existing and emerging wireless communication technologies

Circular polarized (CP) antennas are well suited for long-distance transmission attainment. In order to be adaptable for beyond 5G communication, a detailed and systematic investigation of their important conventional features is required for expected enhancements. The existing designs employing millimeter wave, microwave, and ultra-wideband (UWB) frequencies form the elementary platform for future studies. The 3.4-3.8 GHz frequency band has been identified as a worthy candidate for 5G communications because of spectrum availability. This band comes under UWB frequencies (3.1-10.6 GHz). In this survey, a review of CP antennas in the selected areas to improve the understanding of early-stage researchers specially experienced antenna designers has presented for the first time as best of our knowledge. Design implementations involving size, axial ratio, efficiency, and gain improvements are covered in detail. Besides that, various design approaches to realize CP antennas including (a) printed CP antennas based on parasitic or slotted elements, (b) dielectric resonator CP antennas, (c) reconfigurable CP antennas, (d) substrate integrated waveguide CP antennas, (e) fractal CP antennas, (f) hybrid techniques CP antennas, and (g) 3D printing CP antennas with single and multiple feeding structures have investigated and analyzed. The aim of this work is to provide necessary guidance for the selection of CP antenna geometries in terms of the required dimensions, available bandwidth, gain, and useful materials for the integration and realization in future communication systems

Through Wall Imaging Radar Antenna with a Focus on Opening New Research Avenues

This review paper is an effort to develop insight into the development in antennas for through wall imaging radar application. Review on literature on antennas for use in through wall imaging radar, fulfilling one or more requirements/specifications such as ultrawide bandwidth, stable and high gain, stable unidirectional radiation pattern, wide scanning angle, compactness ensuring portability and facilitating real-time efficient and simple imaging is presented. The review covers variants of Vivaldi, Bow tie, Horn, Spiral, Patch and Magneto-electric dipole antennas demonstrated as suitable antennas for the through wall imaging radar application. With an aim to open new research avenues for making better through wall imaging radar antenna, review on relevant compressive reflector antennas, surface integrated waveguide antennas, plasma antennas, metamaterial antennas and single frequency dynamically configurable meta-surface antennas are incorporated. The review paper brings out possibilities of designing an optimum through wall imaging radar antenna and prospects of future research on the antenna to improve radiation pattern and facilitate overall simple and efficient imaging by the through wall imaging radar