Diversity Reception - Sennheiser EM 550 G2 Instructions For Use Manual

Diversity reception

The two receivers of the EM 550 G2 operate on the "true diversity" principle:
A receiving antenna receives not only the electromagnetic waves which reach
it by a direct path, but also the reflections of these waves which are created
in the room by walls, windows, ceilings and fittings. When these waves are
superimposed, destructive interference occurs, which can also be called "field
strength gaps". Repositioning the receiving antenna can bring a solution.
With mobile transmitters, however (which all radiomicrophones are), the
"field strength gap" will then occur with a different transmitter position.
These "field strength gaps" can only be eliminated with true diversity
receivers.
In true diversity, instead of one antenna and one receiver there are now two
antennas and two receiver sections. The antennas are spatially separated. By
means of a comparison circuit, the receiver section with the strongest RF
signal is always switched to the common AF output. The risk of the
occurrence of "field strength gaps" in both antennas at the same time is
virtually nonexistant.
The receiver display panel shows the active diversity section (I or II) .
Electronic
Control signal
Control signal
switch-over of
Receiver section I AF signal Receiver section II
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