Channel estimation in 802.11g in the presence of Bluetooth interference

In this paper, we provide a model for the Bluetooth (BT) interference and propose interference mitigation techniques at the channel estimation stage in IEEE 802.11g Wireless Local Area Network (WLAN) receivers. BT signal has been modelled as a narrow band tonal interference. Estimation of the BT interference by the Estimation of Signal Parameters using Rotational Invariance Techniques (ESPRIT) algorithm is proposed. The structure of the 802.11g preamble is exploited to define the Difference Terms (DTs). The 802.11g signal is subtracted out in DTs and the ESPRIT algorithm efficiency is improved by operating on non-colored noise environment. The reconstructed interference signal is subtracted from the received time domain signal before getting the Least Square (LS) channel estimates. The proposed ‘ESPRIT-LS’ algorithm is shown to outperform the simple LS channel estimation algorithm in terms of channel estimation Mean Squared Error (MSE) and the Bit Error Rate (BER) for a range of interference power levels.