Table 3 A global comparison between FWT and FFT coarse sensing methods

Better at obtaining a higher P_d which is important to satisfy the required primary user QoS. Used when the primary user QoS is of higher concern

Better at obtaining a lower P_f which is important to achieve better spectral efficiency. Used when the spectral efficiency is of higher concern

The sensing resolution could be simply increased to reach RB resolution by applying further FWT decompositions

To increase the sensing resolution we need to increase the FFT size

An ID algorithm could be applied at each wavelet decomposition stage to reduce the number of FWT operations with an acceptable performance

The ID algorithm is not applicable to FFT where the operation is performed in one stage

In case the LTE receiver is an SDR and has a programmable FFT core, we lose the option of reusing this core which is used in the LTE OFDM receiver to perform spectrum sensing

When the receiver is an SDR with a programmable FFT core, we can simply reuse the same FFT core used in the LTE OFDM receiver to perform spectrum sensing thus reducing complexity