In this paper various layered planar periodic structures which provide miniaturization of planar antennas are proposed and discussed. The proposed designs are based on two concepts, reactive impedance surfaces and complementary periodic structures. In the proposed structures, complementary periodic rings and slots are patterned on the intermediate boundaries of the dielectric layers. A patch an...

In In this paper, two low profile, single fed cavity backed slot antennas providing a circularly polarized (CP) wave are introduced. One of the antennas presents a right-handed CP (RHCP) wave, while the other one offers a left handed CP (LHCP) wave. The proposed antennas consist of a square shaped Substrtae Integrated Waveguide (SIW) cavity incorporatng two couples of radiating slots to radiate...

Analysis and design of the planar microstrip antenna have been discussed in the preceding chapters. Planar microstrip antenna by and large can be considered to have reached its maturity. Development of conformable antennas on non planar surfaces lags behind vis-à-vis planar microstrip antennas. Relatively non planar or microstrip antennas conformable to non planar surfaces are at present topic ...

The bandwidth limitations of resonant, electrically small antennas that fully occupy a spherical volume are well defined by the inverse of the Chu-limit or the lower bound on quality factor. Recently, Gustafsson et al developed lower bounds for the Q of antennas of arbitrary shape. We have previously described antenna designs fully occupying a spherical volume and a cylindrical volume that exhi...

This paper describes very compact MIC magic-Ts and their integration with planar array antennas to realize the advanced antenna modules. The orthogonal transmission modes are effectively used to arrange the preferable port layout of magic-Ts. This flexible port layout of magic-Ts is a practical feature for integration with planar array antennas. The integration of magic-Ts and planar array ante...

Leaky-wave antennas use a traveling wave to radiate continuously along a radiating aperture in order to produce a focused beam of radiation. Planar leaky-wave antennas are particularly attractive since they use simple dielectric layers and/or metallic screens over a grounded substrate layer. A simple source such as a dipole or slot inside the substrate or on the ground plane excites the leaky w...

Monopole antennas have several advantages but for their narrow bandwidth. Broadband planar monopole antennas have all the advantages of the monopole in terms of their cost, and ease of fabrication besides, yielding very large bandwidths. For many applications large bandwidth is required. Recently, many techniques to tailor and optimize the impedance BW of these antennas have been investigated. ...

Abstract ⎯ In this paper a printed dipole antenna and three slot antennas are designed to operate at 10 GHz for use in radar systems. A parametric study of each antenna and comparison between their radiation properties including return loss, bandwidth, directivity, efficiency and radiation patterns for 6-element linear array are introduced. Slot antennas show wider bandwidth, less coupling and ...

The frequency-dependent characteristics of microstrip planar circuits have been previously analyzed using several full-wave approaches. All those methods directly give characteristic of the circuits frequency by frequency. Computation time becomes important if these planar circuits have to be studied over a very large bandwidth. The transmission line matrix (TLM) method presented in this paper ...