WLAN smart antenna with Bluetooth interference reduction

Because of the coexistence of wireless local area network (WLAN) and Bluetooth at the same ISM band, WLAN systems cannot eliminate the interference by Bluetooth in the physical layer by carrier sense multiple access/collision avoidance. A novel smart antenna system for the WLAN systems to suppress the Bluetooth interference is proposed. The proposed smart antenna system employs the property of multi-carrier transmission of an orthogonal frequency-division multiplexing (OFDM) system to eliminate the correlation among the multi-path components, and the direction of arrival (DOA) estimation algorithm can estimate the correct DOAs. In the simulation, we apply the proposed smart antenna to the 802.11 system using OFDM. The simulation results demonstrate a superior performance under Bluetooth interference.