Non-contactless (contact) measurement method

AN2866

20/24

Figure 20.

Coil samples

6.

Characterization of antenna coil samples

The coil samples are characterized using the Hp 8712ET analyzer in reflection mode

and the 7405-901 Eaton/Alitech (singer) 6 cm loop probe. The probe generates a field

and analyzes the response field.

Figure 21.

Coil characterization

7.

Determining the best coil parameter

The average of the two is given by:

8.

less close values depending on the precision required:

–

–

–

9.

Production of antenna coil samples:

ai15824

V

F

13.56 MHz

6.23 µH

6.56 µH

6.88 µH

ai15825

L

ant

L

ant

()

L

ant

5%

+

()

+

2

-----------------------------------------------------

6.72 µH

==