Cisco Cisco Aironet 3500i Access Point Libro blanco
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Cisco CleanAir Competitive
Page 10
We tested using single interferers and multiple interferers in the 2.4GHz band, and single
interferers in the 5GHz band.
interferers in the 5GHz band.
Screen shot from Cisco
This picture shows the successful classification of multiple simultaneous interference sources.
We began with a single 2.4GHz video surveillance camera as our source of interference.
Motorola triggered an alarm for a “continuous wave” but could not identify the device. The Cisco
WCS identified the device as a video camera, located it and indicated that the interference
severity was 98. The Cisco wireless controller UI also displayed the Wi-Fi channel utilization
and air quality as poor.
We began with a single 2.4GHz video surveillance camera as our source of interference.
Motorola triggered an alarm for a “continuous wave” but could not identify the device. The Cisco
WCS identified the device as a video camera, located it and indicated that the interference
severity was 98. The Cisco wireless controller UI also displayed the Wi-Fi channel utilization
and air quality as poor.
With the microwave oven test, Motorola provided two alarms, one at the access point and one
at the sensor, and correctly identified the source. The access point detected the interference at
2437MHz, while the sensor detected interference at 2462MHz. No correlation is provided by
Motorola so the same device showed up as two alarms within the AirDefense system.
at the sensor, and correctly identified the source. The access point detected the interference at
2437MHz, while the sensor detected interference at 2462MHz. No correlation is provided by
Motorola so the same device showed up as two alarms within the AirDefense system.
Cisco detected and identified the interference as a microwave oven from three access points
and reported a single event. It detected which channels were affected, and located the oven.
This information remains available after the interference has passed, for remediation of periodic
interferences.
and reported a single event. It detected which channels were affected, and located the oven.
This information remains available after the interference has passed, for remediation of periodic
interferences.
A DECT cordless phone base station was placed in the environment. The base station produces
interference when it tries to communicate with the handsets, but it is at a lower duty cycle than
an active call. Motorola displayed the interference on the spectrum analysis UI, but could not
identify the source. The low duty cycle was not enough for it to identify. Cisco classified the
source as a “DECT-like phone,” and pinpointed the physical location.
interference when it tries to communicate with the handsets, but it is at a lower duty cycle than
an active call. Motorola displayed the interference on the spectrum analysis UI, but could not
identify the source. The low duty cycle was not enough for it to identify. Cisco classified the
source as a “DECT-like phone,” and pinpointed the physical location.
The duty cycle was increased by adding an active handset to our base station. This time,
Motorola detected the interference at the access point, as well as two sensors, and identified
the source as a “frequency hopper.” Detection was intermittent. Cisco detected and classified
the phone and base station as “DECT-like phone,” and again mapped the physical location.
Motorola detected the interference at the access point, as well as two sensors, and identified
the source as a “frequency hopper.” Detection was intermittent. Cisco detected and classified
the phone and base station as “DECT-like phone,” and again mapped the physical location.
We added two more handsets and made them all active. Motorola classified the source of
interference as a frequency hopper. Detection remained intermittent. We tested the Motorola
using both the Full Scan mode and Interference Scan mode. Detection was intermittent for both
interference as a frequency hopper. Detection remained intermittent. We tested the Motorola
using both the Full Scan mode and Interference Scan mode. Detection was intermittent for both