AKG Acoustics WMS 4000 Microphone User Manual


 
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Shadow loss:
Shadow loss means that the signal path from the transmitter to the antenna is interrup-
ted by an obstacle.
Multipath transmission:
A radio signal travels to the receiver not only along the direct path but also along several
alternative routes as the signal is reflected off or diffracted around all kinds of structures. So
the same signal arrives at the receiver at different points in time and in different conditions.
Diversity systems help to eliminate transmission problems caused by shadow effects or multipath transmission.
Non Diversity
Wireless systems with a non-diversity receiver have to pro-
cess the signal in whatever shape it reaches the antenna.
Even with moderate distances between transmitter and
receiver, this results in more frequent – and therefore very
disturbing – periods of signal dropout.
Dual antenna diversity
When the RF signal level of the antenna path being used
becomes too low, the switching circuit connects the recei-
ver input to the other antenna. If this fails to provide a
higher signal level, the switching circuit reverts to its ori-
ginal position. The disadvantage of this system is that it
only checks whether the RF signal level of the second
antenna is higher once the level at the first antenna is
already too low. Differences in the signal/noise ratio are
not even detected at all.
True diversity technology
In contrast to antenna diversity, true diversity not only
employs two antennas, but two receivers as well. The
switching circuit compares the quality of the two signals
and routes the better signal to the output.
AKG WMS MULTICHANNEL TECHNOLOGY