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www.cooperbussmann.com/wirelessresources
Cooper Bussmann 945U-E Wireless Ethernet Modem & Device Server User Manual
Rev Version 2.14
TX Antenna
Select which antenna port the module will transmit from:
Main Port Only
—Messages are transmitted from the main TX/RX port. The auxiliary
port RX is disabled.
Both (Diversity)
—Both ports will be used to transmit, but not at the same time. It
calculates the best port based on previous transmissions and MAC addressing.
NOTE Broadcast / UDP transmission messages will initially toggle between
the antenna ports, and could result in every second message not being
heard until the module learns which device can be reached through which
antenna port.
Aux Port Only
—Messages will be transmitted via the auxiliary RX port only.
RX Antenna
Same as for TX antenna above, but for the receiver port. Setting to “Both (Diversity)”
will allow a high gain antenna to be connected to the auxiliary “RX” port, which will
give better RX signal gain without increasing the TX gain and possibly pushing it over
the regulatory EIRP threshold.
DTIM Period
(Access point only.) DTIM sets which beacon frames incorporate extra information for
low power sleeping client devices. Normally set this to 1.
RTS Threshold
Request To Send threshold. RTS frames can be used to help avoid radio collisions
between two stations that cannot directly hear each other. Any frame larger than the
RTS threshold bytes will be preceded by an RTS message. The default value of RTS
threshold is 2346, which effectively disables RTS signaling, as this value is larger
than the maximum frame size (fragmentation threshold).
Fragmentation
Threshold
(Client stations only.) The maximum transmission unit (MTU) of data over the radio. If
more than this number of bytes is input into the module, it will be transmitted in more
than one message (fragmented).
Interference
Mitigation
(Access point only.) Interference Mitigation should only be turn on (default is Off) if
using demo whip antennas, or if there is a high level of background interference.
By enabling this option, the radio will dynamically adjust radio parameters to help
mitigate interference based on any background interference. It will reduce the
receiver sensitivity and therefore should only be enabled on paths with a high fade
margin and good signal quality.
Bursting
Selecting this option can increase the data throughput by reducing the overheads
associated with wireless transmissions.
Enable Iperf Server
Enable Iperf Server function in the modem. Iperf is used for performing radio surveys
or radio path testing. See “4.4 Throughput Test.”
Fixed Noise Floor
Allows the radio receiver noise floor (and therefore sensitivity) to be moved above
any interference. This essentially stops the radio from communicating with devices
that have lower signal strength. For use in areas where there is a greater amount of
interference.
Fixed Noise Floor
900MHz FHSS band can have many sources of interference. This interference can sometimes be a problem due
to the way 802.11 devices communicate. Standard 802.11 communications uses a system called “clear channel
assessment” which means the radio will listen before transmission and if the channel is busy it will hold off
regardless of the level of signal. If the background interference is high due to other radio systems or noise, you
can raise the fixed noise floor to compensate. The Channel Utilization page can be used to identify excess noise or
interference.
Raising the noise floor will block out any receive signal levels below the value configured under “Fixed Noise Floor”
on the Advanced Radio Configuration page. The value must be entered as a negative dBm number and should be
at least 8 dB greater than the weakest RSSI of any connected modems, otherwise communications may be lost.