The 3-dB coupler can be used:
? As a decoupled power spliter with a ratio of 1:1
? For the decoupled combining of two transmitters with a
frequency spacing as narrow as desired (at 3 dB loss)
? For the decouped combining of two receivers with frequency
spacing as narrow as desired
? For the decoupled combining of two transmitter/receiver units,
whose integrated duplexers are within the same frequency
? As a frequency-independent 90° phase shifter
? As a component to form combiners
The 3-dB coupler has four ports, two of which are decoupled
from each other. For example, effective power entering into
port 1 is distributed into ports 2 and 3. Port 4 is decoupled and
without power if ports 2 and 3 are ideally matched. In practice
an absorber of suitable power at port 4 is to be planned in
accordance with the mismatch of ports 2 and 3.
Decoupled combining can be achieved via the diagonally
opposite ports 2 and 3 or 1 and 4.
For indoor or outdoor use (IP66).