1. Waveguide - T AE-323 MICROWAVE DEVICES AND ENGINEERING Lecture No 07
Text Book : Microwave Devices and Circuits by Liao
Chapter 4 Section 4-4-1
Instructor: Engr Irfan Ahmed
Class: Avionics 6 (Batch 2)
Number of Slides: 19
Avionics Engineering Department

2. Learning Objectives
Types of Waveguide T’s
E-plane T
H-plane T
Magic T

3. Types of Waveguide T’s
E-plane T
H-plane T
Magic T

4. E-plane Tee
Axis of side arm is parallel to the E-field of the main guide.
If E-plane T is perfectly matched:
If the side arm is the input port:

5. E-plane Tee

6. E-plane Tee
If Input is at port 3 , then Output at port 1 & port 2 is same but out of phase So
As per symmetricity property

7. E-plane Tee
Unitary property
Multiplying
Suppose port 3 is matched

8. E-plane Tee
Subtracting the equations
We get

9. E-plane Tee
Now matrix will result from To

10. E-plane T (Series T)

11. H-plane T (Shunt T)
Axis of side arm is perpendicular to the E-field of the main guide.
If the side arm is the input port:

13. Magic T (Hybrid T)
If two waves of equal magnitude and same phase are fed into port 1 and port 2
output will be zero at port 3 and additive at port 4.
If a wave is fed into port 4 (H arm),
it will be divided equally between port 1 and port 2 of the collinear arms and will not appear at port 3 (E arm).

14. Magic T (Hybrid T)
If a wave is fed into port 3, it will produce an output of equal magnitude and opposite phase at port 1 and port 2. the output at port 4 is zero. That is, S43 = S34 = 0.

15. Magic T (Hybrid T)
If a wave is fed into one of the collinear arms at port 1 or port 2, it will not appear in the other collinear arm at port 2 or port 1 because the E arm causes a phase delay while the H arm causes a phase advance. That is, S12 = S21 = 0.

16. Magic Tee They are used in mixing, duplexing
Example two identical radars transmitters requires Twice more input to the Antenna than Either transmitter can deliver

17. 2 Transmitter Example

18. Summary