Now in an completely revised, updated, and enlarged Second Edition, Small Antennas in Portable Devices reviews recent significant theoretical and practical developments in the electrically small antenna area. Examining antenna designs that work as well as those that have limitations, this new edition provides practicing engineers and upper level and graduate students with new information on: work on improving bandwidth using spherical helix dipoles; work on electromagnetically coupled structures; exact derivation of the Q for electrically small antennas for both the TE and TM modes; and a new simplified Q formula.

Robert C. Hansen, PhD, DEng, has had a long and distinguished career in the aerospace industry. Beginning in 1949, he held key posts in a number of leading aerospace companies, including The Aerospace Corp., STL, Inc. (now TRW), and Hughes Aircraft Co. He is a Fellow of IEEE and IEE and is a member of the National Academy of Engineering. Since 1971, Dr. Hansen has been a consulting engineer for antennas and systems-related problems. The Late Robert Collin, PhD, taught at Case Reserve Western University, where he was chairman of the Department of Electrical Engineering and Applied Physics. He was an invited professor at Pontifical Catholic University of Rio de Janeiro; Telebras Research Center, Brazil; and Beijing University, China. Dr. Collin was the author or coauthor of five books and more than 150 technical papers.

Leseprobe

Preface. 1. Quality Factors of ESA. 1.1 Introduction. 1.2 Chu Antenna Q. 1.3 Collin and Rothschild Q Analysis. 1.4 Thal Antenna Q. 1.5 Radiansphere With Mu and/or Epsilon - TE Modes. 1.6 Radiansphere With Mu and/or Epsilon - TM Modes. 1.7 Effects of Core Losses. 1.8 Q for Spheroidal Enclosures. 2. Bandwidth and Matching. 2.1 Introduction. 2.2 Foster''s Reactance Theorem and Smith Chart. 2.3 Fano''s Matching Limitations and Bandwidth Improvement Factor. 2.4 Matching Circuit Loss Magnification. 2.5 Network and Zo Matching. 2.6 Non-Foster Matching. 2.7 Matched and High Z Preamp Monopoles. 3. ESA: Canonical Types. 3.1 Introduction. 3.2 Dipole Basic Characteristics. 3.3 Partial Sleeve, PiFA, and Patch. 3.4 Loops. 4. Clever Physics But Bad Numbers. 4.1 Contrawound Toroidal Helix. 4.2 Transmission Line Antennas. 4.3 Halo, Hula Hoop, and DDRR Antennas. 4.4 Dielectric Loaded Antennas. 4.5 Meanderline Antennas. 4.6 Cage Monopole. 5. Pathological Antennas. 5.1 Crossed Field Antenna. 5.2 Infinite Efficiency Antenna. 5.3 E-H Antenna. 5.4 TE-TM Antenna. 5.5 Crossed Dipoles. 5.6 Snyder Dipole. 5.7 Loop-Coupled Loop. 5.8 Multiarm Dipole. 5.9 Complementary Pair Antenna. 5.10 Integrated Antenna. 5.11 Q = 0 Antenna. 5.12 Antenna in a NIM Shell. 5.13 Fractal Antennas. 5.14 Antenna on a Chip. 5.15 Random Segment Antennas. 5.16 Multiple Monopoles. 5.17 Switched Loop Antennas. 5.18 Electrically Small Focal Spots. 5.19 ESA Summary. 6. Superdirective Antennas. 6.1 History and Motivation. 6.2 Maximum Directivity. 6.3 Constrained Superdirectivity. 6.4 Bandwidth, Efficiency, and Tolerances. 6.5 Miscellaneous Superdirectivity. 6.6 SD Antenna Summary. 7. Superconducting Antennas. 7.1 Introduction. 7.2 Supercondictivity Concepts for Antennas Engineers. 7.3 Dipole, Loop, and Patch Antennas. 7.4 Phasers and Delay Lines. 7.5 SC Antenna Summary. Appendix A. A World History of Electrically Small Antennas. Appendix B. Definitions of Terms Useful to ESA. Appendix C. Spherical Shell of Eng Material Surrounding A Dipole Antenna. Appendix D. Frequency Dispersion Limits Resolution in Veselago Lens. Subject Index.