Configuring Transmit And Receive Antennas - Cisco M10-RM Software Manual

Configuring Transmit and Receive Antennas

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You cannot configure short or long radio preambles on the 5-GHz radio.
Beginning in privileged EXEC mode, follow these steps to disable short radio preambles:
Command
Step 1 configure terminal
Step 2
interface dot11radio { 0slot/port }
Step 3
no preamble-short
Step 4 end
Step 5 copy running-config startup-config (Optional) Save your entries in the configuration file.
Short preambles are enabled by default. Use the preamble-short command to enable short preambles if
they are disabled.
Configuring Transmit and Receive Antennas
You can select the antenna the wireless device uses to receive and transmit data. There are three options
for both the receive and the transmit antenna:
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Cisco IOS Software Configuration Guide for Cisco Aironet Access Points
6-24
Long—A long preamble ensures compatibility between the wireless device and all early models of
Cisco Aironet Wireless LAN Adapters (PC4800 and PC4800A). If these client devices do not
associate to the wireless devices, you should use short preambles.
Gain—Sets the resultant antenna gain in dB.
Diversity—This default setting tells the wireless device to use the antenna that receives the best
signal. If the wireless device has two fixed (non-removable) antennas, you should use this setting
for both receive and transmit. If the device has three removable antennas, you can use this setting to
have all of them operate in diversity mode
Right—If the wireless device has removable antennas and you install a high-gain antenna on the
wireless device's right connector, you should use this setting for both receive and transmit. When
you look at the wireless device's back panel, the right antenna is on the right.
Middle—If the wireless device has removable antennas and you install a high-gain antenna on
wireless device's middle connector, you should use this setting for receiving only. The antennas
available for transmitting in a three-antenna configuration are the right and left antennas.
Left—If the wireless device has removable antennas and you install a high-gain antenna on the
wireless device's left connector, you should use this setting for both receive and transmit. When you
look at the wireless device's back panel, the left antenna is on the left.
Purpose
Enter global configuration mode.
Enter interface configuration mode for the 2.4-GHz radio
interface.
Disable short preambles and enable long preambles.
Return to privileged EXEC mode.
Chapter 6 Configuring Radio Settings
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