NEUTRIK Xirium Pro Mounting Manual page 2

Line-of-sight + redundant RF path
For a reliable wireless audio link, make sure all XIRIUM PRO
devices have line-of-sight. If a link cannot be established with
line-of-sight, the receiver may be in a drop-out zone.
A drop-out zone is a point where phase cancellation occurs
between the direct signal and the deflected one. Relocating
the transmitter (TX) and/or receiver (RX) can help eliminate
this phase anomaly. The use of a repeater can eliminate this
problem as it provides a redundant RF path to all receivers
within range. The RX receives the identical audio signal from
two different sources (Transmitter and Repeater).
Transmitter signal
RX with Repeater module
Repeater as a redundant RF path
Repeater
signal
Identical audio signal
from two different
sources = redundancy