Polarisation Of A Horn - Chauvin Arnoux ORITEL ANC 100/15 Notice De Fonctionnement

- Rotate by an α
angle, adjust the ATM 100 attenuator located after the wavemeter at A
2
come back to the D
- Carry out these manipulations for several α rotation angle values on either side of the horn and, for
each angle, note down:
∆
= A - A
1 0 1
∆
= A - A
2 0 2
- Plot the ∆
curve in acccordance with a, corresponding to the radiation pattern in polar coordinates
dB
provided.
3.5

Polarisation of a horn

Radiation polarisation can be brought to the fore by simply applying the Malus cosine-squared law well-
known to opticians.
The wave emitted is polarised and linear, since the method of propagation in the waveguide is TE
wave received is linear. If the receiving horn rotates around its axis by an α angle, the power received is
expressed as:
P is the received power without the receiving horn rotating.
0
In that case, attenuation is:
Apply the following diagram:
CF 204
OSG 100 ISO 100 MOD 100
Proceed as in the figure below:
indication on the IR 205.
0
etc.
10 log P
A =
(dB)
P
ATM 100 OND 100
α
P = P cos 2
0
0
= - 10 log (cos
α
2
cos
0
ATM 100
ANC 100/15
0
17
α)
2
R
d
ANC 100/15
Horizontal axis
in order to
2
. The
10
IR 205
TGN 100 + DEN 100