الفهرس 
CHAPTER 1Only 14 pages are availabe for public view
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Abstract
Few years after the early investigation of ultra-wideband (UWB)
wireless system, considerable research efforts have been put into the
design of UWB antennas and systems for communications. These
UWB antennas are essential for providing wireless wideband
communications based on the use of very narrow pulses on the order of
nanoseconds, covering a very wide bandwidth in the frequency domain,
and over very short distances at very low power densities.
The rapidly growing demand for UWB as high data rates wireless
communications technology, since the Federal Communications
Commission (FCC) allocated the bandwidth of UWB from 3.1GHz to
10.6 GHz. Antenna also plays an essential role in UWB system.
However, there are some difficulties in designing UWB antenna as
compared to narrowband antenna. The primary requirement for UWB
antenna is to be able to operate over frequencies which are released by
FCC. Furthermore, the satisfaction of radiation properties and good
time domain performance over the entire frequency range are also
necessary. In this thesis, UWB monopole antenna’s design and analysis
are focused upon. The monopole antenna exhibits omni-directional
pattern where the power is radiated equally in all directions. The
performance parameters such as return loss, radiation pattern of the
UWB hexagonal patch is extensively investigated and carried out. Both
of the results have been demonstrated using simulation and
experimentally whereby all results satisfy the performance under -1 OdB
point from 3.1 GHz to 10.6 GHz.
(of ultra-wideband (UWB.