An Investigation into Using Kalman Filtering for Phase Estimation in Bluetooth Receivers For Gaussian and Non-Gaussian Noise

Gaussian Frequency Shift Keying (GFSK) modulation scheme is used in Bluetooth receivers to achieve a basic data rate of 1Mps. GFSK is a subclass of Continuous Phase Modulation (CPM) where phase is constrained to be continuous during symbol transition which results in enhanced spectral properties, that makes it an attractive modulation in many wireless applications. In this paper, we investigate applying linear Kalman Filter (LKF) to non-coherently track the phase of GFSK modulation scheme in Bluetooth receivers. The paper examines the performance of Linear Kalman Filter for both Additive White Gaussian channel noise (AWGN) and Non-Gaussian Impulsive Noise with IEEE802.11 coexistence. Both technologies operate in the unlicensed 2.4GHz Industrial Scientific Medical (ISM) Band. Mean Square Error (MSE) was used as a measurement for the performance. Experimental results for Linear Kalman Filter for Gaussian channel and Non Gaussian Impulsive Noise are provided.