Channel Planning and RF Design Flashcards

What is the primary goal of channel planning in a WLAN deployment?

Answer: Minimize co-channel interference between access points

Channel planning aims to minimize co-channel interference by ensuring APs using the same channel are spaced far enough apart that their signals do not significantly overlap.

In the 2.4 GHz band, how many non-overlapping 20 MHz channels are available in the United States?

Answer: 3

Only channels 1, 6, and 11 are non-overlapping in the 2.4 GHz band in the US, giving exactly 3 usable non-overlapping channels.

What is co-channel interference (CCI) in a WLAN environment?

Answer: Interference between access points operating on the same channel

CCI occurs when two or more APs share the same channel and their coverage areas overlap, causing them to contend for airtime and degrade performance.

Which channel planning strategy assigns the same channel to APs that are sufficiently separated to prevent interference?

Answer: Frequency reuse planning

Frequency reuse planning deliberately reuses the same channels at APs spaced far enough apart so their coverage cells do not interfere with each other.

In the 5 GHz band using 20 MHz channels, approximately how many non-overlapping channels are available in the US across UNII-1, UNII-2, UNII-2e, and UNII-3?

Answer: 25

The US 5 GHz band provides approximately 25 non-overlapping 20 MHz channels when all available UNII sub-bands are considered, making it far richer than 2.4 GHz.

What is Adjacent Channel Interference (ACI) in wireless networking?

Answer: Interference between APs on channels that partially overlap in frequency

ACI occurs when APs use channels that are close but not identical in frequency, causing partial spectral overlap that degrades signal quality.

Which tool is most commonly used to visualize RF channel assignments and coverage across a floor plan during the design phase?

Answer: RF planning / heat map software

RF planning software (such as Ekahau or iBwave) generates predictive heat maps that overlay channel assignments and coverage patterns onto floor plans before deployment.