Adaptive guard bands for spectrum pooling

Cognitive Radio (CR) techniques provide the capability to use or share the spectrum in an opportunistic manner. Spectrum Pooling is a key technique of CR, which enables public access to spectral ranges of licensed frequency bands which are seldom used by overlaying a secondary rental user (RU) to an existing licensed user (LU). However, the interference between LU and RU is severe in multipath wireless channel. In the paper, a CR system with LU and RU co-existing is constructed by Spectrum Pooling technique and an adaptive algorithm of guard bands is proposed to mitigate the mutual interference between LU and RU by adaptive deactivating one or more sub-channels of RU. Results show the intercarrier interference (ICI) of LU is improved by applying the adaptive algorithm.