User's Manual

Solid Object
Reflected Signal
Refracted Signal
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Signal Strength And Signal Quality:
Signal strength and signal quality are
not the same. Reflections can
interfere with intended signals even
though the strength of the signal will
still measure as acceptable.
Familiar examples of this are "ghosts"
on a television screen caused by
reflections off buildings or hills; the TV
antenna is picking up plenty of signal
strength, but the signal quality is poor.
If you see good received signal
strength, but the Link Quality value is
poor, you may be seeing the affect of
reflected signals. Changing the
locations of wireless network
components may clear up the
problem.
RF Interference
Interference can affect the SMI wireless network in several ways. The most common is a loss of data,
which results in waveform dropouts. Many devices can cause RF Interference by broadcasting or
producing noise in the 2.4 GHz to 2.4835 GHz range. These devices include microwave ovens, airport
radar systems, microwave communication systems, and other nearby electronic devices. The frequency
hopping radio attempts to minimize this problem by jumping to another frequency every 200 milliseconds.
Part Number 062-0983-01 Rev C page 3 - 9