What is meant by defected ground structure?
A defected ground structure (DGS), is a purposefully created defect on the ground plane of a printed microstrip board. It is typically created in the form of an etched-out pattern on the ground plane. DGS is a simplified form of Electromagnetic Band Gap (EBG) structure.
What is defected microstrip structure?
Defected microstrip structure (DMS) is made by etching certain slot patterns in the microstrip line, and it exhibits the properties of slow-wave, rejecting microwaves in certain frequencies that are similar to the defected ground structure (DGS) but without any manipulation of the ground plane.
What is meant by microstrip patch antenna?
It is a kind of internal antenna. They are mostly used at microwave frequencies. An individual microstrip antenna consists of a patch of metal foil of various shapes (a patch antenna) on the surface of a PCB (printed circuit board), with a metal foil ground plane on the other side of the board.
Why is ground structure defected?
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.
What is meant by radiation pattern of an antenna?
The radiation pattern or antenna pattern is the graphical representation of the radiation properties of the antenna as a function of space. That is, the antenna’s pattern describes how the antenna radiates energy out into space (or how it receives energy).
Why is patch antenna used?
The patch antenna is mainly practical at microwave frequencies, at which wavelengths are short enough that the patches are conveniently small. It is widely used in portable wireless devices because of the ease of fabricating it on printed circuit boards.
What is parasitic array?
A parasitic array consists of a single driven element connected to the feedline, and other elements which are not, called parasitic elements. It is usually another name for a Yagi-Uda antenna. However the term “phased array” is sometimes used to mean an ordinary array antenna.
What is quarter wave antenna?
Only a single radiating edge remains with this design which reduces the radiation pattern directivity compared with a half wavelength patch. This rectangular microstrip antenna design is known as a quarter wave microstrip patch or half patch antenna.
What causes antenna Sidelobes?
The mainlobe shape and width, as well as the near sidelobe levels, are determined by the wavelength, the antenna reflector size, and the tapering of its illumination. More distant sidelobes are caused by imperfection in the antenna and blockage of radiation by the feed horn, its supports (Fig. 3.3), radome, and so on.