Digital Signal Processing Reference
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Fig. 3.10 The normalized
energy distributions of the
transmit-signal and effective
target-returns across different
subchannels in ( a ) Scenario I
and ( b ) Scenario II
carrier at which the target response is stronger, and thus makes the effective
target-return more prominent along that subcarrier.
As a further confirmation, we did a similar analysis with values of
{ ε S ,l }
and
ε T ,l /( L 1
{
}
for Scenario II. Results are shown in Fig. 3.10 (b). Observing the
two left-most vertical bars, we again notice that the transmitted-signal energy was
amplified along the first subchannel after the waveform design. The two right-most
vertical bars indicate a noticeable redistribution of the effective target-energies
among the different subchannels. After the adaptive waveform design, we found
that the normalized values of
0 ε T ,l )
l
=
{
ε T ,l }
{
}
changed from
0 . 5414 , 0 . 0775 , 0 . 3811
to
{
. This reconfirms our conclusion that the Pareto-optimal
waveform design tries to further enhance the stronger target-returns. Moreover,
since we kept the noise-energy fixed and varied only the target-energy over dif-
ferent subchannels, we can extend our conclusion to assert that the solution of the
Pareto-optimal design redistributes the energy of the transmitted signal by putting
the most energy to that particular subcarrier in which the signal-to-noise ratio is the
strongest.
0 . 7447 , 0 . 0775 , 0 . 1779
}
 
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