Coarse spectrum sensing for LTE systems

Spectrum sensing is one of the most challenging tasks required of a cognitive radio receiver. In this paper, we consider the first stage of spectrum sensing, where it is required to perform the sensing as fast as possible and with an acceptable performance under different channel conditions. The target signal to be sensed is a Long Term Evolution (LTE) signal. We first propose sensing the whole LTE signal bandwidth using the Fast Wavelet Transform (FWT) algorithm and then compare it to the Fast Fourier Transform (FFT)-based algorithm in terms of complexity and performance. A new algorithm is proposed that provides an intelligent stopping criterion for the FWT sensing to further reduce its complexity. This algorithm shows a major advantage for using FWT. We also propose a novel algorithm to go even deeper in the LTE signal band to sense at multiples of a Resource Block (RB) resolution and explain the challenges associated with the proposed algorithm.