09-01-2014, 12:13 PM
Simple Waveform for UWB Communication
ABSTRACT
In this paper, the simple waveform is satisfied the UWB
definition and spectral masks for the indoor and outdoor
limits. The rectangular passband, modulated rectangular,
modulated Gaussian, rectangular doublet, Gaussian dou-
blet and Gaussian monocycle waveforms are considered.
The PSD and parameters of each optimized waveforms are
showed. The optimized results are discussed in the conclu-
sion.
INTRODUCTION
Recently, ultra wideband (UWB) radio technology has
become an important topic for microwave communica-
tion because its potential is low cost and low power con-
sumption properties [1]. UWB is different from other ra-
dio frequency (RF) technologies. Instead of using a nar-
row carrier frequency, UWB transmits pulses of power
spectral density (PSD) in the range of the ultra wide fre-
quency spectrum. The Federal Communication Commis-
sion (FCC) [2] in US specified that UWB has a frequency
spectrum ranging from 3.1 to 10.6 GHz. The FCC defined
the UWB signal as those which have a fractional band-
width greater than 0.20 or occupies bandwidth greater than
500 MHz.
WAVEFORM MODEL
The rectangular passband, modulated rectangular, mod-
ulated Gaussian, rectangular doublet, Gaussian doublet
and Gaussian monocycle waveforms are considered. The
waveform is assumed to be voltage signal. For obtaining
the continuous component of PSD, the binary PAM with
balance binary data independent identically distributed
random sequence is considered.
OPTIMIZATION
The waveforms models is optimized for UWB commu-
nication. The UWB definition by FCC is considered [2].
The condition of fL and fH are set to 3.1 GHz ≤ fL <
fH ≤ 10.6 GHz. Each waveform must has fractional band-
width greater than 0.20 or occupies bandwidth greater than
500 MHz. After that, Each waveform is satisfied the FCC
spectral masks for indoor and outdoor limits. The three
assumptions for good UWB signal waveform are consider.
First is high bandwidth for reducing the effect of multipath
fading [10]. Next is high amplitude for increasing the ef-
ficiency of peak detection receiver. Final is high average
power for increasing the signal to noise ratio (SNR). Then,
each waveform is optimized for maximum bandwidth, am-
plitude and average power in the frequency range from 3.1
to 10.6 GHz. For the optimization, the solution of fre-
quency is 0.01 GHz, the time is 0.01 ns and the amplitude
is 0.01 V.
CONCLUSIOIN
In this paper, the simple waveform is satisfied the UWB
definition and spectral masks for the indoor and outdoor
limits. The rectangular passband, modulated rectangular,
modulated Gaussian, rectangular doublet, Gaussian dou-
blet and Gaussian monocycle waveforms are considered.
From the optimization results, the rectangular passband
waveform obtained the maximum bandwidth, amplitude
and average power. It can consider to be the upper band or
the best case of UWB waveform. For the comparison be-
tween the modulated rectangular and Gaussion waveform,
the modulated rectangular obtained wider bandwidth for
the indoor and outdoor limits. The modulated Gaussion ob-
tain the higher amplitude for the indoor and outdoor limits.
For the indoor limit, the modulated rectangular waveform
obtain more average power while the modulated Gaussion
waveform obtain more average power for the outdoor limit.