An engineer performs a wireless site survey of a multi-floor building for 2.4-GHz and 5-GHz bands. The customer wants to identify non-802.11 sources of interference. Which survey measurement must be…

Channel utilization measures the percentage of airtime consumed by 802.11 transmissions and cannot identify or characterize interference from non-802.11 devices.

Spectrum analysis uses a dedicated hardware radio (such as a Cisco CleanAir-enabled AP or an external USB spectrum analyzer) to sweep the frequency band and record all RF energy, regardless of whether it originates from an 802.11 device. This is the only method capable of identifying non-802.11 interferers such as microwave ovens, Bluetooth radios, analog video cameras, and cordless phones. Without spectrum analysis, non-802.11 interference sources would appear only as an elevated noise floor with no identifiable source.

Signal-to-noise ratio quantifies received signal quality relative to the noise floor but provides no information about the source, frequency, or type of interfering devices.

Co-channel interference specifically describes 802.11 transmissions from other BSSs operating on the same channel and does not account for interference from non-802.11 sources.