Int J Elec & Comp Eng

ISSN: 2088-8708

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Smart monitoring information system based on RF 433 Mhz (SMIS) (Hicham Ouldzira)

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The (1) is given by interpolation with the Newton method, and presents the following correlation

performance reaches 99.94%, the following table gives a summary of these performances:

Table 2. Goodness of fit

SSE

R-square

Adjusted R-square

RMSE

0.166

0.9994

0.9991

0.1052

Where SSE is Sum squared error performance function, R-square is the square of the correlation between the

response values and the predicted response values. It is also called the square of the multiple correlation

coefficient and the coefficient of multiple determination, RMSE (Root Mean Squared Error) is known as the

fit standard error and the standard error of the regression.

The measures that have been taken on a wire alloy copper 2mm diameter for the RF module

depending on the transmission distance.

Table 3. This table presents measurements of RF’s range and antenna’s length

Number of measurestaken

Antennalength(cm)

RF433MHz Range (m)

25

0,1

0,67

24

0,2

1

23

0,3

1,29

22

0,4

1,55

21

0,5

1,61

20

0,6

1,9

19

0,7

2,18

18

0,8

2,48

17

0,9

2,77

16

1

3,11

15

1,1

3,33

14

1,2

3,58

13

1,3

3,65

12

1,4

3,72

11

1,5

4,06

10

1,6

4,47

9

1,7

4,96

8

1,8

5,5

7

1,9

5,98

6

2

6,49

5

2,2

7,55

4

2,4

8,61

3

2,6

9,66

2

2,8

10,53

1

3

14,78

Figure 4. Communication range vs RF433MHZ antenna lentgh