Recently, ultra wideband (UWB) radio technology has be-come an important topic for microwave
communication because of its low cost and low power consumption potentials [1]-[3]. The UWB is
different from other radio frequency (RF) technologies. UWB transmits very short pulse and power
spectral density (PSD) in the range of ultra wide frequency spectrum instead of using narrow band
radio frequency in traditional RF technologies. The UWB is a unique and new usage of recently
legalized frequency spectrum. The FCC specified that UWB signal has frequency spectrum ranging
from 3.1 GHz to 10.6 GHz [4], and have a fractional bandwidth equal or greater than 0.20, or occupied bandwidth equal or greater than 500 MHz. The fractional and occupied bandwidth are defined as