NetComm NP7042 - Manual (Page 6)

www.netcomm.com.au Rev.1 - YML654
Page 6 NP7042 - Wireless LAN USB Adaptor
11 Mbps Operation
The NetComm NP7042 - Wireless LAN USB Adaptor supports a maximum 11 Mbps data
transfer rate. When the adaptors transmit (TX) rate is set to Auto, the adaptor automatically
shifts to a 5.5, 2 or 1 Mbps data rate when unable to maintain a high quality connection at 11
Mbps. When the adaptor detects improved signal strength, it shifts to an increased data rate, up
to the maximum 11 Mbps.
The following factors can dynamically alter the data rate:
■
signal strength between the access point and adaptor,
■
the ratio of good transmitted packets to attempted transmitted packets that fall below a
threshold, or -
■
the adaptor finds a higher transmit rate with another AP or it encounters an unspecified data
rate.
Note: An 11 Mbps data transfer rate should only be anticipated in coverage areas where
the Scan tool (part of the Wireless LAN Monitor Utility) has been used to determine
the strength and quality of the signal between the adaptor and an access point.
Physical obstructions and numerous devices operating in close proximity to one another
negatively impact the ability to maintain an 11 Mbps access point association.
Signal Range
WLAN devices are designed to operate over a radius of 100 meters indoors and 300 metres
outdoors. Obstructions such as walls, ceilings, floors, office equipment, and furniture can reduce
this range. The following example or just some factors that affect the signal range of your
Wireless network.
■
Obstructions. The Wireless LAN radio signal can penetrate through ceilings and walls.
However, each wall or ceiling the signal must pass through to reach other WLAN devices
will reduce the effective range your Wireless LAN.
You should also keep the depth of the obstructions to a minimum. Take an example of a wall
that is half a metre thick. For a radio signal going through the wall, at a forty degree angle, it
must pass through almost one metre of material. At a two degree angle, this increases to over
14 metres! Position adaptors and access points so that the signal will travel straight through
a wall or ceiling for better reception.
Position your adaptors and access points so as to minimise the number and depth of
obstructions and always position your adaptors and access points so that the signal passes
through drywalls or open doorways and not through metallic materials.