Method even if he has full information on


A common method used in chaos engineering is  direct-sequence spread-spectrum (DSSS)
technique which require good  periodic
variation properties ,good correlation,a 
wideband spectrum, initial condition must be sensitive to improve the
security at physical layer. Studies show that 
if an intruder may possibly recover a 
chaotic sequences by a method called blind estimation which will use the
data given from the different sequences to identify the symbols period given
from the this information from your 
original data. We can enhance this security issue by creating using a
varied period according to the behavior of the chaotic spread in the
communication system. How this works exactly is the information given from the
system is given in a variable symbol period and is  multiplied with a chaotic sequence to perform
the spread-spectrum process. Below are different examples of different discrete-time
models that show the synchronization, and analyzation  for a spreading scheme with variable symbol
periods  as well as a despreading scheme
with sequence. We cover a series of Multi-access performance of white Gaussian
noise (AWGN) which  is calculated by
both  numerical computation and
theoretical derivation . After this we compare and contrast the computer and
actual simulations to verify that received data is correct our obtained results
point out that our proposed technique can protect the DSSS systems against the
detection of symbol period from the intruder, even if he has full information
on the used chaotic sequence

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 Spreading scheme with variable bit period

Block diagram demonstrates a spreading scheme with a pulse
chain that has a variable inter-pulse intervals. We used  {pl}, as the variable interval pulse
generator (VIPG) The input we used is the 
{xk} to stand for the chaotic sequence. Which is sampled at each
triggered input pulse.  (1)pl=P(t?tl),
with  (2)P(t)={10?t??,0 Then the  tl is the when you generate the lth pulse
and  the 
output sample xl is then converted into a positive integer ?l.This
happens by using a  transformation
function example (?l=f(xl)).Once  f( · )
is determined the sequence {xl} varies 
range is discovered and the  xmin
& xmax, {?l} is then in direct 
correlation to the range 
?min=f(xmin)=0,?max=f(xmax)=?m.So in order to determine the function
f( · ), we had to usea fixed value for ?m. After we choose the value the  xmin, xmax of the function is then divided
into (?m+1) value intervals, xmin+j?,xmin+(j+1)?,with j varying from 0 to ?m
and ? being a constant defined by(3)?=(xmax?xmin)/(?m+1).Once the input number
xl falls in the range of xmin+j?,xmin+(j+1)?, the value for the other
source  value  ?l can finally be determined for example:
(4)?l=f(xl)=?xl?xmin??,Depending on the value of ?l,  will determine  (l+1)after that the pulse is created at the
output of the VIPG at the tl+1 given by (5)tl+1=tl+(?+?l)?,? is the chip period
of the chaotic sequence {xk} and ? is a fixed integer and the value is fixed.