System and method for active scanning in multi-channel Wi-Fi system

摘要

It is possible to shorten channel monitoring periods of unoccupied channels during Wi-Fi discovery by verifying whether or not a message indicating the presence of a Wi-Fi AP has been detected prior to the probe timer reaching a medium channel time (MedChannelTime). For example, STAs detecting some channel activity during the clear channel assessment may nevertheless discontinue monitoring a Wi-Fi Channel when no messages indicating the presence of a Wi-Fi AP are detected prior to expiration of the MedChannelTime. Messages indicating the presence of a Wi-Fi AP may include any Wi-Fi messages sent from or destined for a Wi-Fi AP, while excluding probe requests and non-Wi-Fi messages.

主权项

1. A method for actively scanning a Wi-Fi network, the method comprising:
sending, by a station (STA), a probe request message over a first channel in a multi-channel wireless local area network (WLAN); monitoring, by the STA, the first channel for probe response messages; setting, by the STA, a probe timer; detecting, by the STA, at least some channel activity prior to the probe timer reaching a minimum channel time (MinChannelTime); discontinue monitoring, by the STA, of the first channel when the probe timer reaches a medium channel time (MedChannelTime) unless a message indicating the presence of a Wi-Fi access point (AP) is detected on the first channel after sending the probe request message and prior to the probe timer reaching the MedChannelTime; and monitoring, by the STA, the first channel until the probe timer reaches a maximum channel time (MaxChannelTime) when at least one message indicating the presence of a Wi-Fi AP is detected on the first channel after sending the probe request message and prior to the probe timer reaching the MedChannelTime, wherein the MedChannelTime is in-between the MinChannelTime and the MaxChannelTime.