Identifying Wireless Interference from Channel Overlap

The scenario describes intermittent connectivity for IoT devices on a hospital wireless network, supported by an exhibit showing overlapping Wi-Fi channels. The core issue is interference caused by multiple access points (APs) operating on the same or adjacent channels within the same RF environment.

Frequency Overlap Analysis: In the 2.4 GHz band, standard channel spacing is 20 MHz. However, only channels 1, 6, and 11 are non-overlapping. If APs are configured on channels 1, 2, 3, etc., their signal spectra overlap significantly. This creates co-channel interference (CCI) and adjacent-channel interference (ACI), forcing devices to retransmit packets due to collisions and noise. This results in the reported intermittent connectivity and poor performance for IoT devices, which often have limited radio capabilities compared to smartphones or laptops.

Evaluating Other Options:

• Poor RSSI (A): While weak signal strength can cause issues, the specific mention of channel configurations in the exhibit points directly to spectrum management rather than distance or obstruction.
• Incorrect channel size (B): While wider channels (e.g., 40 MHz) reduce available non-overlapping channels, the fundamental problem depicted is the overlap itself, not necessarily the width setting alone.
• Roaming misconfiguration (D): Roaming issues typically manifest as sticky clients or slow handoffs between APs. They do not explain the general intermittent connectivity across the network segment unless specifically tied to AP coordination, which is less direct than the interference shown.

The comments highlight that channel overlap is the primary culprit in such scenarios, particularly in dense environments like hospitals where many APs are deployed.