Год выпуска: 2012 Автор: Umair Zia,Syed Irfan Ali and Syed Talha Ahmed Издательство: LAP Lambert Academic Publishing Страниц: 76 ISBN: 9783659298370
Описание
Problems mostly encounter is that of weak cellular signals strength in areas like Basements, Railway Tunnels and Hill Stations etc. In all these areas due to different kinds of hurdles signal strength decreases due to fading, multi path propagation and due to other huge size obstacles.In this way some of the voice data is lost and the rest of voice data has degraded voice quality. Data transmission at higher rates requires wider bandwidths for the elements constituting a communication link. This requires wide band antennas be designed and used. The dimensions of a log-periodic dipole antenna(LPDA), when expressed in terms of wavelength, vary with frequency, it’s usually exhibit different radiation properties at different frequencies, and can be designed for any band, HF to UHF, and can be built to meet the amateur’s requirements at nominal cost.
