Radio Module Slots; Single Or Dual-Radio Operation; Operating Modes; Spatial Multiplexing - Cisco AIR-AP1252AG-A-K9 Hardware Installation Manual

Chapter 1 Overview

Radio Module Slots

The access point has two radio module slots: Slot 0 and Slot 1 (see
with the 2.4-GHz radio module and slot 1 can only be used with the 5-GHz radio module.
New radio configuration changes are associated with the specific module slot in which the radio module
is located. When the default radio settings are changed, the radio modules should not be moved to a
different slot. After configuration changes are made, moving the radio modules to a different modules
slot requires that you re-configuring the radio settings for that slot.

Single or Dual-Radio Operation

The access point supports single or simultaneous dual radio (draft IEEE 802.11n version 2.0) operation
using 2.4-GHz and 5-GHz radio modules. Each radio module contains an integrated radio with three
antenna connectors. A blank module is supported for single radio access point configurations.
The 2.4-GHz radio supports 802.11b, 802.11g, and 802.11n modes of operation. The 2.4-GHz radio also
supports 1 or 2 transmitting antennas and up to 3 receiving antennas.
The 5-GHz radio supports 802.11a and 802.11n modes of operation. The radio supports the Unlicensed
National Information Infrastructure (UNII-1, UNII-2, and UNII-3), and the European
Telecommunications Standards Institute
The 5-GHz radio also supports 1 or 2 transmitting antennas and up to 3 receiving antennas.

Operating Modes

The 2.4-GHz radio module supports four operating modes:
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The 5-GHz radio module supports three operating modes:
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Spatial Multiplexing

The radio modules can support two transmitters to achieve faster data rates for a given bandwidth. This
technique is called multiple input multiple output (MIMO) and relies on the premise that, via multi-path,
two transmitted signals take different paths to the receivers. Using special data packet features allows
the receivers to distinguish between the two transmitted signals and increases the access point data rate.
OL-8247-03
802.11b single transmit antenna
802.11g single transmit antenna
802.11n HT-20 MHz with dual transmit antennas
802.11n HT-40 MHz with dual transmit antennas
802.11a single transmit antenna
802.11n HT-20 MHz with dual transmit antennas
802.11n HT-40 MHz with dual transmit antennas
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industrial, scientific and medical (ETSI/ISM) frequency bands.
Cisco Aironet 1250 Series Access Point Hardware Installation Guide
Hardware Features
Figure 1-1). Slot 0 can only be used
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