3.3.1. Channels and Frequencies

Frequency Bands:

Non-overlapping 2.4 GHz Channels: Only 1, 6, and 11 don't overlap. Each channel uses 22 MHz of spectrum but is only 5 MHz apart from neighbors.

Channel Width: Wider channels = more throughput but fewer non-overlapping options:

• 20 MHz: Standard, most channels available
• 40/80/160 MHz: Higher throughput, fewer channel options, 5 GHz preferred

DFS (Dynamic Frequency Selection): Many 5 GHz channels (in the US, 52–64 and 100–144) share spectrum with radar. An AP on one of them must listen for radar and move to another channel when it detects it.

Transmit power: More isn't always better. Turning every AP's power up makes APs on the same channel hear each other (co-channel interference) and keeps clients clinging to a distant AP. Dense deployments use lower power and more APs.