Electromagnetic Band Gap Structures in Antenna Engineering

Transcription

1 Electromagnetic Band Gap Structures in Antenna Engineering FAN YANG University of Mississippi YAHYA RAHMAT-SAMII University of California at Los Angeles Hfl CAMBRIDGE Щ0 UNIVERSITY PRESS

2 Contents Preface Acknowledgements Abbreviations Introduction 1.1 Background 1.2 Electromagnetic band gap (EBG) structures EBG definition EBG and metamaterials 1.3 Analysis methods for EBG structures 1.4 EBG applications in antenna engineering Antenna substrates for surface wave suppressions Antenna substrates for efficient low profile wire antenna Reflection/transmission surfaces for high gain antennas FDTD method for periodic structure analysis 2.1 FDTD fundamentals Introduction Yee's cell and updating scheme Absorbing boundary conditions: PML FDTD excitation Extraction of characteristic parameters 2.2 Periodic boundary conditions Fundamental challenges in PBC Overview of various PBCs Constant k x method for scattering analysis 2.3 Guided wave analysis Problem statement Brillouin zone for periodic waveguides Examples 2.4 Plane wave scattering analysis Problem statement Plane wave excitation Examples

3 vi Contents 2.5 A unified approach: hybrid FDTD/ARMA method A unified approach for guided wave and scattering analysis ARMA estimator Examples Projects 54 EBG characterizations and classifications Resonant circuit models for EBG structures Effective medium model with lumped LC elements Transmission line model for surface waves Transmission line model for plane waves Graphic representation of frequency band gap FDTD model Near field distributions inside and outside the frequency band gap Frequency band gap for surface wave propagation Dispersion diagram Surface wave band gap In-phase reflection for plane wave incidence Reflection phase EBG reflection phase: normal incidence EBG reflection phase: oblique incidence Soft and hard surfaces Impedance and reflection coefficient of a periodic ground plane Soft and hard operations Examples Classifications of various EBG structures Project 85 Designs and optimizations of EBG structures Parametric study of a mushroom-like EBG structure Patch width effect Gap width effect Substrate thickness effect Substrate permittivity effect Comparison of mushroom and uni-planar EBG designs Polarization-dependent EBG surface designs Rectangular patch EBG surface Slot loaded EBG surface EBG surface with offset vias An example application: PDEBG reflector Compact spiral EBG designs Single spiral design 103

4 Contents vii Double spiral design Four-arm spiral design Dual layer EBG designs Particle swarm optimization (PSO) of EBG structures Particle swarm optimization: a framework Optimization for a desired frequency with a +90 reflection phase Optimization for a miniaturized EBG structure General steps of EBG optimization problems using PSO Advanced EBG surface designs Space filling curve EBG designs Multi-band EBG surface designs Tunable EBG surface designs Projects 124 Patch antennas with EBG structures Patch antennas on high permittivity substrate Gain enhancement of a single patch antenna Patch antenna surrounded by EBG structures Circularly polarized patch antenna design Various EBG patch antenna designs Mutual coupling reduction of a patch array Mutual coupling between patch antennas on high dielectric constant substrate Mutual coupling reduction by the EBG structure More design examples EBG patch antenna applications EBG patch antenna for high precision GPS applications EBG patch antenna for wearable electronics EBG patch antennas in phased arrays for scan blindness elimination Projects 153 Low profile wire antennas on EBG ground plane Dipole antenna on EBG ground plane Comparison of PEC, PMC, and EBG ground planes Operational bandwidth selection Parametric studies Low profile antennas: wire-ebg antenna vs. patch antenna Two types of low profile antennas Performance comparison between wire-ebg and patch antennas A dual band wire-ebg antenna design 169

5 viii Contents 6.3 Circularly polarized curl antenna on EBG ground plane Performance of curl antennas over PEC and EBG ground planes Parametric studies of curl antennas over the EBG surface Experimental demonstration Dipole antenna on a PDEBG ground plane for circular polarization Radiation mechanism of CP dipole antenna Experimental results Reconflgurable bent monopole with radiation pattern diversity Bent monopole antenna on EBG ground plane Reconflgurable design for one-dimensional beam switch Reconflgurable design for two-dimensional beam switch Printed dipole antenna with a semi-ebg ground plane Dipole antenna near the edge of a PEC ground plane Enhanced performance of dipole antenna near the edge of an EBG ground plane Printed dipole antenna with a semi-ebg ground plane Summary Projects 200 Surface wave antennas A grounded slab loaded with periodic patches Comparison of two artificial ground planes Surface waves in the grounded slab with periodic patch loading Dipole-fed surface wave antennas Performance of a low profile dipole on a patch-loaded grounded slab Radiation mechanism: the surface wave antenna Effect of the finite artificial ground plane Comparison between the surface wave antenna and vertical monopole antenna Patch-fed surface wave antennas Comparison between a circular microstrip antenna and a patch-fed SWA Experimental demonstration Dual band surface wave antenna Crosspatch-fed surface wave antenna Modified crosspatch-fed surface wave antenna for dual band operation Projects 236 Appendix: EBG literature review 238 Index 261