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R

=

W

T

p

fv

p

cv

w

v

,

(12)

where

p

cv

— is the probability of correct detection of the synchronization

code in the “Test” mode at the threshold value

ε

v

, and

p

fv

— is the

probability of false detection of the synchronization code in the message

symbols in the “Test” mode at

ε

v

. The value

R

should be as small as

possible.

Table 5 shows the values

R

at the selected value

ε

s

and at different

ε

v

and

w

v

.

Table 5

Values

R

in the “Test” mode

Values

R

at

p

r

= 0

.

1

,

n

= 16

,

b

= 145

and

ε

s

= 1

ε

v

w

v

= 1

w

v

= 2

w

v

= 3

w

v

= 4

w

v

= 5

0 6.13

10

6

5.05

10

10

4.158

10

14

3.424

10

18

2.819

10

22

1 3.75

10

5

1.89

10

8

9.532

10

12

4.803

10

15

2.420

10

18

2 0.000197 5.22

10

7

1.383

10

9

3.665

10

12

9.708

10

15

3

0.00085

9.71

10

6

1.108

10

7

1.265

10

9

1.444

10

11

4

0.00291

0.000114

4.441

10

6

1.735

10

7

6.780

10

9

5

0.00785

0.000827

8.721

10

5

9.192

10

6

9.689

10

7

6 0.016933

0.00385

0.000875

0.000199

4.524

10

5

In Table 5, for example, the pairs

(

ε

v

, w

v

)

are selected for the

synchronization system in such a way that at the required value

R

T

the value

R

does not exceed the predetermined

R

T

(

R

R

T

).

In this example, at the given acceptable probability value

R

T

= 10

6

,

R

=

{

5

.

22

10

7

; 1

.

108

10

7

; 1

.

735

10

7

; 9

.

689

×

10

7

}

are selected for

the pair values

(

ε

v

, w

v

) =

{

(2

,

2)

,

(3

,

3)

,

(4

,

4)

,

(5

,

5)

}

, respectively.

The probability of outcoming from the states “Search” and “Test” in

the case of correct detection of the synchronization code is as follows:

p

tc

=

p

cs

(1

F

)

(1

q

w

s

)

(1

q

)

(

p

cv

)

w

v

,

(13)

where

q

= (1

p

cs

) (1

F

)

.

(14)

Table 6 shows the values

p

tc

for the chosen value

ε

s

and different

ε

v

and

w

v

.

The values

p

tc

=

{

0

.

454; 0

.

602; 0

.

681; 0

.

718

}

correspond to the selected

values

R

. It should be noted that while increasing the value of the pair

(

ε

v

, w

v

)

from (2, 2) to (3, 3) it increases

p

tc

(from 0.602 to 0.454) by 0.148,

but while increasing it from the value (3, 3) to (4, 4), it increases

p

tc

only

126 ISSN 0236-3933. HERALD of the BMSTU. Series Instrument Engineering. 2015. No. 2