I recently came across “nzyme” [1], a WiFi Intrusion Detection System (IDS). Nzyme does focus on WiFi-specific attacks, so it does not care about payload but inspects the 802.11 headers that escape traditional, wired IDSs. It was not terribly hard to get it running on a Raspberry Pi using a Panda USB WiFi adapter.
Article Link: https://isc.sans.edu/diary/rss/27288