Publicité
Les langues disponibles
Les langues disponibles
Ultrasounds
Moduson table
Ref :
223 008
1.2 Step 2: Protocol
Directivity of ultrasonic waves
Determination of the reception peak:
The reception peak is obtained by finding the receiver position on the arc of circle that yields
the highest amplitude for the received signal.
The oscilloscope settings are 0.1 V/div for vertical amplification and 0.1 msec/div for
horizontal sweep. The periodical signal is then very narrow and its amplitude is better
readable. The amplitude is 0.3 V.
The amplitude peak of the signal sensed by the receiver corresponds to the zero graduation.
Sound transmission cone:
The ultrasonic waves are emitted by the transmitter in a zone to be determined.
Record the value a of the received signal amplitude for a variable value θ of the angle
defining the position of the ultrasonic receiver (θ is negative on the left of 0 and positive on
the right.
The following results are obtained:
a
0,09 0,12 0,15 0,19 0,23 0,27 0,28 0,3 0,3 0,28 0,26 0,22 0,20 0,17 0,13 0,10 0,08
in V
θ
-40
-35
in °
The corresponding graph is shown below:
ENGLISH
-30
-25
-20
-15
a
0,35
0,3
0,25
0,2
0,15
0,1
0,05
0
-40
-30
-15
-10
-5
0
5
10
0
15
30
42
15
20
25
30
θ
40
35
40
Publicité
