A method for detecting a source of interference creates a sorting table according to distances between station devices and an access point (AP) device, and the created sorting table is sent to the AP device. The AP device determines upon a target device from the sorting table and controls the target device to acquire status and distance information between target device and AP device and send the information to the AP device. A value ε is computed according to the information sent by the target device and the calculated value ε is compared with a preset value k. The source of an interference, which affects the signal sent by the AP device, is calculated based on the comparison, and the AP device applies appropriate de-noising to the signal according to the determined interference source.