Passive Planar Microwave Devices

The aim of this book is to highlight some recent advances in microwave planar devices. The development of planar technologies still generates great interest because of their many applications in fields as diverse as wireless communications, medical instrumentation, remote sensing, etc. In this book, particular interest has been focused on an electronically controllable phase shifter, wireless sensing, a multiband textile antenna, a MIMO antenna in microstrip technology, a miniaturized spoof plasmonic antipodal Vivaldi antenna, a dual-band balanced bandpass filter, glide-symmetric structures, a transparent multiband antenna for vehicle communications, a multilayer bandpass filter with high selectivity, microwave planar cutoff probes, and a wideband transition from microstrip to ridge empty substrate integrated waveguide

Defected Ground Structure: Fundamentals, Analysis, and Applications in Modern Wireless Trends

Slots or defects integrated on the ground plane of microwave planar circuits are referred to as Defected Ground Structure. DGS is adopted as an emerging technique for improving the various parameters of microwave circuits, that is, narrow bandwidth, cross-polarization, low gain, and so forth. This paper presents an introduction and evolution of DGS and how DGS is different from former technologies: PBG and EBG. A basic concept behind the DGS technology and several theoretical techniques for analysing the Defected Ground Structure are discussed. Several applications of DGS in the field of filters, planar waveguides, amplifiers, and antennas are presented

Impedance Transformers

Non

Novel substrate integrated waveguide filters and circuits

The main work in this thesis is to explore novel microwave filters with more compact size and improved performance by taking advantage of new substrate integrated waveguide (SIW) structures, such as the ridge substrate integrated waveguide, half mode substrate integrated waveguide (HMSIW) and SIW with complementary split ring resonators (CSRRs). This thesis therefore presents the following topics: 1. Development of a design strategy to convert from a conventional ridge waveguide configuration with solid walls to the SIW counterpart, and the design of a bandpass filter based on the ridge SIW with the proposed design method. 2. Development of a ridged HMSIW to reduce the physical size of the HMSIW by loading the HMSIW with a ridge, and application of the ridged HMSIW to the design of compact bandpass filters. 3. Development of a broadside-coupled complementary split ring resonator and a capacitively-loaded complementary single split ring resonator to reduce the size of SIW with conventional CSRRs, and application of the proposed modified structures in the design of SIW and HMSIW filters with improved compactness and performance. 4. Investigation of the application of the complementary electric-LC (CELC) resonator in SIW filters with improved stopband performance, and development of a cascaded CELC resonator to further enhance the out-of-band performance

Wideband and UWB antennas for wireless applications. A comprehensive review

A comprehensive review concerning the geometry, the manufacturing technologies, the materials, and the numerical techniques, adopted for the analysis and design of wideband and ultrawideband (UWB) antennas for wireless applications, is presented. Planar, printed, dielectric, and wearable antennas, achievable on laminate (rigid and flexible), and textile dielectric substrates are taken into account. The performances of small, low-profile, and dielectric resonator antennas are illustrated paying particular attention to the application areas concerning portable devices (mobile phones, tablets, glasses, laptops, wearable computers, etc.) and radio base stations. This information provides a guidance to the selection of the different antenna geometries in terms of bandwidth, gain, field polarization, time-domain response, dimensions, and materials useful for their realization and integration in modern communication systems

3D Electromagnetic Analysis and Optimization of Metamaterial Constructed by SRR Using the MOGA Algorithm for Performance Improvement

The study presents 3D electromagnetic analysis and optimization of metamaterial constructed split ring resonator. The analysis was carried out under electromagnetic analysis conditions by using electromagnetic boundary conditions master and slave. The operating frequency range, in other words the performance characteristic, has been analysed from 1 GHz to 20 GHz. The split-ring resonator design has been analysed on triple co-axes in accordance with its actual use. Surface current density, electric field strength and magnetic field strength values were examined in the analysis. Metamaterial based split-ring resonators are used in many fields. Today, it has many applications as measurement and sensor or as antenna in 5G applications. In order to obtain a suitable design at high frequencies, micron-level designs are required. Newly developed objective functions are presented in the study. In this study, good results were obtained with an optimized SRR design by using multi-objective genetic algorithm in the range up to 20 GHz that can achieve negative refractive index capacity. These results are presented in the study with the relationship between permittivity and permeability. Furthermore, when the results obtained from the design are examined, it is seen that it is suitable for wireless applications. Performance improvement have been carried out SRR negative refractive index capacity which before has 11 GHz was increased to 15.5 GHz

Metamaterial

In-depth analysis of the theory, properties and description of the most potential technological applications of metamaterials for the realization of novel devices such as subwavelength lenses, invisibility cloaks, dipole and reflector antennas, high frequency telecommunications, new designs of bandpass filters, absorbers and concentrators of EM waves etc. In order to create a new devices it is necessary to know the main electrodynamical characteristics of metamaterial structures on the basis of which the device is supposed to be created. The electromagnetic wave scattering surfaces built with metamaterials are primarily based on the ability of metamaterials to control the surrounded electromagnetic fields by varying their permeability and permittivity characteristics. The book covers some solutions for microwave wavelength scales as well as exploitation of nanoscale EM wavelength such as visible specter using recent advances of nanotechnology, for instance in the field of nanowires, nanopolymers, carbon nanotubes and graphene. Metamaterial is suitable for scholars from extremely large scientific domain and therefore given to engineers, scientists, graduates and other interested professionals from photonics to nanoscience and from material science to antenna engineering as a comprehensive reference on this artificial materials of tomorrow