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7. Where possible, try to ensure an uninterrupted line-of-sight between
nodes. Avoid obscuring objects (e.g. metal pillars, posts, sign) near the
antenna. A close object obscures a wider range of solid angle.
8. It is important to understand that the environment may change over time
due to new equipment or machinery being installed, building construction,
etc. If new obstacles exist between the End Device and Meter, antenna
angle may need to be re-adjusted and/or the unit has to be relocated.
9. An IEEE 802.15.4 wireless network will not work under water. Wet
condition (e.g. in heavy rainfall) may exhibit some degradation. In most
cases, water droplets on or close to the antenna are more serious than
the rain itself. Humidity can affect radio performance as well.
10. Reduced performance scenario:
a. A large building may have few obstructions between nodes but large
amount of metallic paneling that cause reflections.
b. A small domestic installation may have numerous brick walls between
nodes in individual rooms.
c. An office building may have metalized dry-wall partitions together with
mezzanine ceilings.
Figure 5.1 Operation in Buildings
Data is sent through radio signal at 2.4 GHz. Radio signals are
electromagnetic waves, hence the signal becomes weaker the
further it travels.
While radio waves can penetrate some solid materials like a wall,
they can diminish more than when a direct line-of-sight between the
transmitting and receiving antenna exist.
Therefore, it is generally a good idea to place Meter at the center
while End Devices are located about the same distance away from
it. If possible, keeping clearance around the line of site will improve
performance as well.
