US Patent 11855914 Performing distributed dynamic frequency selection using a shared cache

Embodiments herein describe a group of APs that uses a shared radar cache to select a new channel after vacating a current channel when performing dynamic frequency selection (DFS). The group of APs can set aside memory to store status information about the DFS channels in the frequency band. For example, when one AP detects a radar event (and has to vacate a DFS channel), the AP updates an entry for that channel in the shared radar cache. The APs can also query the cache to determine a new channel after vacating its current channel. That is, the shared radar cache may store the most recent radar events occurring in a channel. In this manner, the APs can select a new channel that has little or no recent radar events, which reduces the likelihood the AP will have to vacate the new channel.