5.1General Deployment Guidelines (continued)

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 your End Device and Coordinator, 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.

End Device

STORAGE ROOM

MANUFACTURING

MANUFACTURING

AREA

Coordinator

AREA

 

PC

 

CONTROL ROOM

 

 

OFFICE

OFFICE

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 Coordinator 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.

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Omega Vehicle Security zSeries manual Control Room Office, Operation in Buildings