FACULTY OF ENGINEERING
( TELECOMMUNICATION ENGINEERING )
MULTIMEDIA COLLEGE EASTERN
( ASSIGNMENT 1 )
NAME : TENGKU PUTRI NURAIN BINTI TENGKU ISMAIL
ID NO. : DTETEF08040056
IC NO. : 901225145760
DATE OF SUBMIT: NOVEMBER 2008
i. Introduction to Ground Wave 3
ii. Surface Wave 4
iii. Effect of Frequency 5
iv. Effect of The Ground 6
v. Effect of Polarization 7
vi. References 8
Introduction to Ground Wave
The ground wave used for radio communications signal propagation on the long, and medium wave bands for local radio communications.
[pic][pic][pic]Ground wave propagation is particularly important on the LF and MF portion of the radio spectrum. Ground wave radio propagation is used to provide relatively local radio communications coverage, especially by radio broadcast stations that require to cover a particular locality.
Ground wave radio signal propagation is ideal for relatively short distance propagation on these frequencies during the daytime. Sky-wave ionospheric propagation is not possible during the day because of the attenuation of the signals on these frequencies caused by the D region in the ionosphere.
In addition to this there is surface wave. This tends to follow the curvature of the Earth and enables coverage to be achieved beyond the horizon. Beyond the horizon the direct and reflected waves are blocked by the curvature of the Earth, and the signal is purely made up from the diffracted surface wave. It is for this reason that surface wave is commonly called ground wave propagation.
The radio signal spreads out from the transmitter along the surface of the Earth. Instead of just travelling in a straight line the radio signals tend to follow the curvature of the Earth. This is because currents are induced in the surface...