The Atheros AR9390 is a commercial IEEE 802.11n wireless chipset developed by Qualcomm Atheros that is widely used in consumer-grade routers and network interface cards, notable for its compatibility with modified firmware drivers — most prominently the Atheros-CSI tool — that expose raw Channel State Information (CSI) measurements to researchers. Its significance to the WiFi sensing field lies in its ability to provide subcarrier-level amplitude and phase data across multiple antenna streams (supporting MIMO configurations) without requiring specialized or costly hardware, making it one of the most accessible platforms for device-free human behavior recognition, occupancy detection, and crowd counting research. It is commonly deployed in devices such as TP-Link routers running OpenWrt-based firmware and paired with Intel 5300 NICs in complementary setups, and is often referred to interchangeably as the AR9390 or simply the Atheros 9390 chipset across the CSI sensing literature.
Source Papers
- A Survey on Human Behavior Recognition Using Channel State Information ↗ — A Survey on Human Behavior Recognition Using Channel State I
- Device-Free Passive Identity Identification via WiFi Signals ↗ — Device-Free Passive Identity Identification via WiFi Signals
- Device-free occupancy detection and crowd counting in smart buildings with WiFi-enabled IoT ↗ — Device-free occupancy detection and crowd counting in smart
- Understanding and Modeling of WiFi Signal Based Human Activity Recognition ↗ — Understanding and Modeling of WiFi Signal Based Human Activi