Vega VEGAPULS 56K, Инструкция по эксплуатации

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VEGAPULS 56K 5
Time transformation
Pulse sequence
Meas. dis-
tance
emission - reflection - receipt
1 ns
278 ns
t t
Product description
system as impulse packets with a pulse
duration of 1 ns and pulse breaks of 278 ns;
this corresponds to a pulse package
frequency of 3,6␣ MHz. In the impulse breaks
the antenna system operates as receiver.
Signal running periods of less than one mil-
lionth of a second must be processed and the
echo pictures must be evaluated in a fraction
of a second.
VEGAPULS radar sensors can reach this in a
special procedure of time transformation which
spreads more than 3,6 million echo pictures
per second in a slow-motion picture, then
freezes and processes them.
Hence it is possible for the VEGAPULS 56
radar sensors to process the slow-motion
pictures of the sensor environment precisely
and in detail in cycles of 0,5 up to 1 second
without using very time consuming frequency
analysis (e.g. FMCW) necessary for other
radar principles.
Virtually all products can be measured
Radar signals physically react similar to visible
light. According to the quantum theory they
penetrate empty space. Hence they are not
bound such as e.g. sound to a conductive
product (air) and spread like with light velocity.
The radar signals react to two electrical
primary quantities:
- the electrical conductivity of a substance.
- the dielectric constant of a substance.
All products which are electrically conductive
reflect radar signals very well. Even only
slightly conductive products ensure a suffi-
cient signal reflection for a reliable measure-
ment.
All products with a dielectric constant
ε
r
of
more than 2,0 reflect radar impulses suffi-
ciently (note: air has a dielectric constant
figure
ε
r
of 1).
The signal reflection increases with the con-
Reflected radar power dependent on the dielectric
constant figure of the measured product
2
0
0
10
25 %
40 %
5
10
5 %
20
30
40
50
%
4 6 8 12 14 16 18
20
r