User guide

Ubee Interactive Deploying and Troubleshooting the Wireless Network
Ubee DDW366 Dual-Band Concurrent Advanced Wireless Gateway Subscriber User Guide • September 2014 84
5. Use the attenuation value from the materials table above in the following formula:
Formula:
(Transmit Power, use -30dBm) – (Receiver Sensitivity, use RSSI value) =
Allowable Free Space Loss
Allowable Free Space Loss ÷ Materials Attenuation Value =
Optimal Distance in Feet Between the DDW366 and a Wireless Client
Example:
(-30dBm) - (-67dBm) = 37dBm (allowable free space loss for a 54Mbps connection)
37dBm ÷.24db/foot (for open space) = 154.16 feet
6. Once you know the optimal feet distance between individual wireless clients and the
DDW366, you may resolve and prevent some performance issues.
7. Check the wireless signal strength and speed of the computer connected wirelessly to
the DDW366. Instructions for checking speeds are provided for both a Windows and
Mac computer in the table below. If the wireless computer is not connected, refer to
Connecting a Wireless Device on page 13.
Double Pane Coated Glass 13dB 20dB
Bullet Proof Glass 10dB 20dB
Steel / Fire Exit Door 13dB to 19dB 25dB to 32dB
Human Body 3dB 6dB
Trees (Note 2) 0.15dB / foot 0.3dB / foot
Note 1: Different types of concrete
materials are used in different
parts of the world and the
thickness and coating differ
depending on whether it is used in
floors, interior walls, or exterior
walls.
Note 2: The attenuation caused
by trees varies significantly
depending upon the shape and
thickness of the foliage.
Attenuation Considerations
Material
Attenuation
2.4GHZ 5GHz