TOPIC 2

WAVEGUIDE AND COMPONENTS

COURSE LEARNING OUTCOME (CLO)

CLO1

• Explain clearly the generation of microwave, the effects of microwave radiation and the propagation of electromagnetic in a waveguide and its accessories

CLO2

• Apply given mathematical equations or Smith Chart to solve problem related to microwave propagation.

CLO3

• Handle systematically the related microwave communication equipment in performing the assigned practical work.

2.1.1 Propagation Mode

Upon completion of this topic, students should be able to:

• Explain with an illustration types of propagation mode:

a. Transverse Electromagnetic (TEM)

b. Transverse Electric (TE)

c. Transverse Magnetic(TM)

• Relate the propagation of electromagnetic wave in terms of:

a. Poynting vector

b. Boundary condition

c. Spherical and plane wave

electromagnetic wave.

• Merupakan ayunan medan elektrik (E) dan medan magnet (H) yang merambat didalam ruang bebas serta bersudut tepat antara satu sama lain.

• Merambat dengan kelajuan cahaya

3x10^8 m/s.

• Wave propagating in free space is known as the TEM mode (Transverse Electromagnetic).

• TEM Wave (Transverse Electromagnetic)

have magnet field component, electric field and propagation direction that perpendicular between one another.

propagation of electromagnetic wave.

• Electromagnetic (EM) waves propagate in transverse modes.

• THREE (3 ) types :

i) Transverse electromagnetic (TEM)

ii) Transverse electric (TE)

iii) Transverse magnetic (TM)

Types of Propagation Mode

Illustration

• The common mode used to describe EM propagation is the TEM, or Transverse ElectroMagnetic, mode, where neither the electric field nor the magnetic field of the wave is in the direction of propagation

• Wave propagating in free space is known as the TEM mode (Transverse Electromagnetic).

• TEM Wave (Transverse Electromagnetic)

have magnet field component, electric field and propagation direction that perpendicular between one another.

• A mode whose electric field vector is normal to the direction of propagation.

• TE modes may be useful modes in waveguides. In an optical fiber, TE and TM modes correspond to meridional rays.

Mode TE ( Transverse Electric )

– The electric field at right angles (perpendicular) to the direction of propagation and the magnetic field components in line with the direction of propagation.

– TE mode are also known as E mode

• A mode whose magnetic field vector is normal to the direction of propagation

Mode TM ( Transverse Magnetic)

• Magnetic field at right angles (perpendicular) to the direction of propagation, while the electric field components in line with the direction of propagation.

• TM mode are also known as H mode

• Method of Microwave Propagation in wave guide is a "zig-zag. “

• There are two forms of propagation of the effect of:

– velocity of propagation in wave guide less compared with

propagation in free space

– wavelength less compared electromagnetic

wave cross due to

propagation from reflection method need not just normal

component but also component in propagation

direction whether electric field or magnetic field depends

on how wave mode propagated in the waveguide.

Poynting Vector

• Electromagnetic waves carry energy as they travel through empty space. There is an energy density associated with both the electric and magnetic fields.

• Poynting vector represents the directional energy flux density of an electromagnetic field.

• It is named after its inventor John Henry Poynting

• Dipole radiation of a dipole vertically in the page showing electric field strength (colour) and Poynting vector (arrows) in the plane of the page.