AR9287
One of the wireless LAN chips from Qualcomm Atheros.
This chip was released in 2010, so it is quite old.
2.4GHz band
2x2 MIMO
IEEE 802.11n
This is the chip used in TP-Link TL-WN881ND N300 (V1) wireless LAN card.
The Atheros AR9287 is a highly integrated single-chip solution for 2.4 GHz 802.11n-ready WLANs to enable high-performance 2x2 MIMO configurations for applications demanding robust link quality and maximum throughputand range.
https://gyazo.com/94f9418acbd212a4aa0cddddbfbf2c34 http://datasheet.jp/pdf/943104/AR9287.html