VEGA VEGAPULS 51V…54V - Manual (Page 4)

4 VEGAPULS 51 V … 54 V
Product description - Function
1 Product description
1.1 Function
Ra dio d etection a nd r anging: Radar.
VEGAPULS radar sensors are used for non-
contact and continuous distance
measurement. The measured distance
corresponds to a filling height and is
provided as level.
Meas. principle:
emission – reflection – receipt
Smallest 5,8 GHz radar signals are emitted
from the antenna of the radar sensor as short
pulses. The radar impulses reflected by the
sensor environment and the product are
received by the antenna as radar echoes.
The running period of the radar impulses
from emission to receipt is proportional to the
distance and hence to the level.
The radar impulses are emitted by the
antenna 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. Si-
gnal running periods of less than one millionth
of a second must be processed and the
echo pictures must be evaluated in a fraction
of a second.
Hence it is possible for the VEGAPULS 50
radar sensors to process the slow-motion
pictures of the sensor environment precisely
and in detail in cycles of 0,5 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 conductive
product (air) and spread like light with light
velocity.
Time transformation
Meas.
distance
emission - reflection - receipt
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.
1 ns
278 ns
Pulse sequence