Decision feedback equalization for Bluetooth systems

Gaussian Frequency Shift Keying modulation has been chosen as the modulation technique for the physical layer of Bluetooth. Bluetooth is a standard for low cost and low power wireless communications between various mobile devices. The optimal demodulation of a GFSK signal involves an extremely complex Viterbi decoder. Therefore designers have opted for the noncoherent detection of GFSK which uses a frequency discriminator, followed by symbol by symbol detection. Here, we describe a decision feedback equalizer to be added after the discriminator. The DFE receiver gives gains in excess of 2 dBs. We also describe how to increase the current data rate of a Bluetooth system by increasing the symbol rate and not the alphabet size.