Phase and Group velocity
Lecture #11 &
Phase velocity
The phase velocity is a speed at which a point of fixed phase propagates, which is not
always the speed at which EM information travels.
Its a speed at which shape of wave is moving
Its an ordinary sp
Reflection and refraction of
wave by the ionosphere
Lecture # 29 & 30
The mechanism of reflection and refraction of radio waves by the
ionosphere
is very much a function of frequency.
The amount of refraction that occurs depends on three main factors:
1.
PROPAGATION CONSTANT
LECTURE # 07
Phase constant
The rate at which phase changes with respect to distance for any instant of time
is called phase constant.
Unit is rad/ m
Also called wave number.
Let suppose the wave propagating in +ve z direction
Reducti
Lecture#25
Atmosphericregion
Engr.SaimaHafeez
Earth's atmosphere varies in density and
composition as the altitude increases above the
surface.
The atmosphere is divided into five layers. It is
thickest near the surface and thins out with
heightuntiliteve
Time harmonic wave equation
Lecture #09
The wave equation for conducting medium is
Now eq: for H is
Assume direction of propagation is z and E is x polarized field
Put in equation (2)
This is second order equation and linear homogeneous differential equa
Poyntings Theorem
Lecture # 14
Poyntings Theorem
In order to find the power in a uniform plane wave, it is necessary to develop a
power theorem for the electromagnetic field known as the poynyings theorem
Expression of Poyntings theorem can be obtained b
PLANE EARTH REFLECTION
LECTURE # 26
For elevated transmitting and receiving antennas within line of sight of each other,
the direct and ground reflected wave combine to produce the resultant signal.
For a smooth plane, finitely conducting earth the magnit
AttenuationFactorforIonospheric
Propagation
Lecture#33
COLLISION FREQUENY
The collision frequency defines the rate with which electrons
collide with neutral particles in the earths atmosphere or
ionosphere .
AT 90 Km , collision frequeny is 1 MHz (upto en
MEHRAN UNIVERSITY OF ENGINEERING & TECHNOLOGY
FRM-001/00/QSP-004
Dec. 01, 2001
Tentative Teaching Plan
DEPARTMENT OF TELECOMMUNICATION ENGINEERING
Name of Teacher: Engr. Saima Siddiqui
Subject:Electromagnetic Waves & Radiating Systems
Batch:11TLYear: 3rd