# Folded Unipole Antennas: Theory and Applications

by: Jeremy K. Raines

**Abstract:**Folded Unipole Antennas delivers expert, up-to-date engineeringinformation for applying folded antennas technology to a varietyof new applications, including detuning, ECM (electronic countermeasure), cellular, and biomedical. Offering never-before published mathematical equations and configurations, this one-stop resource saves readers hours of research.

Full details

## Table of Contents

**A.**ABOUT THE AUTHOR**B.**Preface**C.**Acknowledgments**1.**Introduction**2.**The Simplest Configuration**3.**The Gamma Match Antenna and the Two-Segment Folded Unipole**4.**The Double Gamma Match Antenna**5.**The N-Segment Folded Unipole**6.**The Most General Configuration**7.**Characteristic Impedance**8.**Reradiation and Detuning**9.**Arrays of Folded Unipoles**10.**Synergy

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## Expanded Table of Contents

**A.**ABOUT THE AUTHOR**B.**Preface**C.**Acknowledgments**1.**Introduction- Introducing the Folded Unipole Antenna
- A Brief History
- A Golden Age of Antenna Analysis
- The Beginning of the Golden Age: Transmission Line Theory
- The Zenith of the Golden Age: Antenna Theory
- The Simple Elegance of Antenna Theory
- The Loaded Monopole Antenna
- The End of the Golden Age: Numerical Methods
- Method of Moments for Simple Antennas and Antenna Arrays
- MoM for Antennas with Multiple Wire Junctions
- The Perils of Large Matrices
- Conclusions
- Symbols Used in This Chapter

**2.**The Simplest Configuration- Introduction
- Essential Features of the Configuration
- The Analysis by Roberts
- The Analysis by Leonhard, Mattuck, and Poté
- The Analysis by King and Harrison
- Equations at the Top of the Folded Unipole
- Equations at the Base of the Folded Unipole
- Matrix Formulation
- Radiated Field and Power
- Input Impedance and Current
- Efficiency
- Being Selective About Examples and Displaying Results
- Examples of Short Folded Unipole Antennas
- Examples of Tall Folded Unipole Antennas
- Conclusions
- Symbols Used in This Chapter

**3.**The Gamma Match Antenna and the Two-Segment Folded Unipole- Introduction
- Essential Features of the GMA and 2SFU
- Equation at the Top of the GMA
- Equations at the Base of the GMA
- Equations at the Boundary Between the Segments of the GMA
- Matrix Equation for the Currents on the GMA
- Radiated Field and Power for the GMA
- Input Impedance and Current for the GMA
- Efficiency of the GMA
- Examples of the GMA with Fold Height as the Primary Variable
- Examples of the GMA with Variable Terminating Reactance and Fold Height
- Examples of the GMA with Both Terminating Reactances Variable
- Equations at the Top of the 2SFU
- Equations at the Base of the 2SFU
- Equations at the Boundary Between the Segments of the 2SFU
- Matrix Equation for the Currents on the 2SFU
- Examples of the 2SFU with Fold Height as the Primary Variable
- Examples of the 2SFU with Variable Terminating Reactance and Fold Height
- Examples of the 2SFU with Two Terminating Reactances as Continuous Variables
- Conclusions
- Symbols Used in This Chapter

**4.**The Double Gamma Match Antenna- Introduction
- Equation at the Top of the 2GMA
- Equations at the Base of the 2GMA
- Equations at the Boundary z = h 1
- Equations at the Boundary z = h 2
- Matrix Equations for Currents on the 2GMA
- Example: 0.3 Wavelength 2GMA with a 0.2 Wavelength Fold
- More Examples: A Variable Length Antenna
- Conclusions
- Symbols Used in This Chapter

**5.**The N-Segment Folded Unipole**6.**The Most General Configuration**7.**Characteristic Impedance- Introduction
- Hallén’s Definition of Common Mode Characteristic Impedance
- Schelkunoff’s Definition of Common Mode Characteristic Impedance
- Characteristic Impedance According to Fundamental Transmission Line Theory
- Quasi Static Log Potential Theory
- Characteristic Impedance of a Single Circular Cylinder
- Characteristic Impedances of Two Parallel Cylinders
- Characteristic Impedances of N Parallel Cylinders
- The Inverted Unipole
- Conclusions
- Symbols Used in This Chapter

**8.**Reradiation and Detuning- Introduction
- Current Induced by an Incident Electromagnetic Wave
- Full Length Detuning
- Examples of Full Length Detuning
- Lower Section Detuning
- Examples of Lower Section Detuning
- Upper Section Detuning
- Examples of Upper Section Detuning
- MidSection Detuning
- Examples of MidSection Detuning
- Additional Detuning Configurations
- Conclusions
- Symbols Used in This Chapter

**9.**Arrays of Folded Unipoles- Introduction
- The Complete Electromagnetic Field of the Folded Unipole Antenna
- Complete Fields of Forward Traveling Current Waves
- Complete Fields of Reverse Traveling Current Waves
- Current Induced by the Exact Electromagnetic Field
- Voltage Induced by the Exact Electromagnetic Field
- Electromagnetic Coupling Between Array Elements
- Transformation for the Radiated Electromagnetic Field
- An Array of Series-Fed Monopole Antennas
- An Array of Folded Unipole Antennas
- Arrays of Folded Unipoles with N Elements
- An Array of Active Folded Unipole Antennas
- Electromagnetic Coupling Factor for Arbitrary Cross Sections
- Conclusions

**10.**Synergy

**Book Details**

**Title: **Folded Unipole Antennas: Theory and Applications

**Publisher: **

**Copyright / Pub. Date: **2007 The McGraw-Hill Companies

**ISBN: **9780071474856

**Authors:****Jeremy K. Raines**
is a full-time consultant,working on various projects involving electromagnetics and antennas.

**Description: **
Folded Unipole Antennas delivers expert, up-to-date engineeringinformation for applying folded antennas technology to a varietyof new applications, including detuning, ECM (electronic countermeasure), cellular, and biomedical. Offering never-before published mathematical equations and configurations, this one-stop resource saves readers hours of research.