This document outlines a project to design a 180-degree hybrid coupler. It discusses the limitations of conventional 180-degree hybrid designs in terms of compactness and bandwidth. It then proposes several novel design methodologies to address these limitations, including using a Wilkinson power divider design, phase reversal methods, folded line configurations, and artificial transmission lines with left-handed materials. The goal is to develop a more compact and broadband 180-degree hybrid coupler design.

1. LOGO
EENG 541 Project:
180°-Hybrid Coupler
Prepared by / Ahmed Mahfouz Marzouk
Presented to/ Dr. Amr Safwat

2. Outline:
 INTRODUCTION.
 PROBLEM.
 METHODOLOGY
 Wilkinson-Power-Divider based Design.
 Phase reversal Design using CPW Inverter
 Compact Folded Line
 Artificial Transmission Lines
 Using Left-Handed Materials
 CONCLUSION.
 REFERENCES.

3. Introduction:
The 180° hybrid is a 4 port network widely used in
RF and Microwave Circuits
Applications:
 Balanced Mixers.
 Balanced Amplifiers.
 Power Multipliers / Dividers
 Antenna Feeding Networks

4. Introduction:
Advantages over 3-port lossless balun:
In-phase and Out-of-phase power splitting while maintaining:
 Port-to-Port Isolation
 Ports Matching
Balanced Circuits require
HYBRID RINGS

5. Introduction:
The 180° hybrid is a 4 port network widely used in
RF and Microwave Circuits
Applications[2]:
 Balanced Mixers.
 Balanced Amplifiers.
 Antenna Feeding Networks
 Power Multipliers / Dividers
Implementation:
rat-race hybrid as the most popular way.

6. PROBLEM:
The 180°-Hybrid Limitations:
 Compactness
 Bandwidth
 THE 270° SECTION
 The resulting 1.5 λ is often
large especially in MMIC app.
 The 270°-section has the
largest phase variation versus
frequency, since the phase variation is proportional to the
line length (∂ф/ ∂ω α ℓ)

7. Methodology:[1]
Novel Hybrid derived from WILKINSON Power
Divider (WPD).
Transmission Line Model of the Novel hybrid:

8. Methodology:[1]
The resistor replacement with a 4th port of an
equal characteristic impedance
MAIN ADVANTAGE: Reduced Size compared to
conventional Rat-Race Hybrid

9. Methodology[2]:
PHASE REVERSAL Method
 270°-section replacement with a “-90°” section.
 The “-90°”-section realization:
 A 90° Microstrip line.
 A Co-Planar Waveguide phase inverter.

10. Methodology[3]:
Compact Folded Line Configurations:
 Rat-Race Configuration using folded line geometry:

11. Methodology[3]:
Compact Folded Line Configurations:
 Rat-Race Configuration using folded line geometry:
 Design Equations: (Using Even-Odd Analysis for single C-
Section Rat-Race Hybrid) :

12. Methodology[3]:
Compact Folded Line Configurations:
 Rat-Race Configuration using folded line geomtry:
 Design Equations: (Using Even-Odd Analysis for single C-
Section Rat-Race Hybrid) :
 Result 

13. Methodology:
Artificial Transmission Lines (ATLs) [4]:
 270°-section replacement with a “-90°” section.
 The “-90°”-section realization:
 Left-Handed material: realizing an artificial lumped-
element TL section.

14. Methodology:
Artificial Transmission Lines (ATLs) [4]:
 270°-section replacement with a “-90°” section.
 The “-90°”-section realization:
 Left-Handed material: realizing an artificial lumped-
element TL section.

15. Methodology:
Artificial Transmission Lines (ATLs) [4]:
 270°-section replacement with a “-90°” section.
 The “-90°”-section realization:
 Left-Handed material: realizing an artificial lumped-
element TL section.

16. Conclusion:
180° hybrids are still to be optimized
Rat-Race Implementation of a 180 hybrid is a
challenging in PCB technology.
Problem: BW and Size especially the (3 λ /4)
section.
Solutions:
 WPD-based Design [1]
 Using CPW Phase Inverter [2]
 ATL Section [4]
 Folded Line Configuration[3][5]

17. REFERENCES

18. Thank You
Questions?

19. LOGO

20. Paper 1: Affiliation
Ning Yang, Member, IEEE, Christophe Caloz,
Fellow, IEEE, and Ke Wu, Fellow, IEEE.
 University: The École Poly-technique de
Montréal; The Polytechnical School of Montreal.

21. Paper 1
Broadband Compact 180 Hybrid
Derived From the Wilkinson
Divider