Low Complexity FFT Based Spectrum Sensing in Bluetooth System

In this paper, the authors propose a complexity reduced spectrum sensing technique for Bluetooth to find channels free from the use of other communication devices in 2.4 GHz ISM band. By exploiting the spectrum characteristics of interference sources, the proposed scheme detects the availability of channels by comparing the Power Spectrum Density (PSD) with a threshold. To reduce the implementation complexity, the PSD is calculated by means of fast Fourier transform and linear interpolation. The threshold for the detection is determined to maximize the detection probability.