Collision Avoidance Spectrum Sharing Technique Using GFDM for Cognitive Wireless Ad-hoc Networks

This paper describes a novel spectrum sharing technique for cognitive wireless ad-hoc networks. To avoid interference caused by joint spectrum usage it is proposed to utilize the Generalized Frequency Division Multiplexing (GFDM), which is a digital multiplexing method candidate for 5G networks. Every peer-to-peer link is established using one of the subcarriers of the GFDM signal, so every node can be connected to as many its one-hop neighbors without spectrum overlapping, as many subcarriers there are configured in the GFDM signal. The GFDM waveform, formed digitally, can be modified on-line to adjust frequency usage depending on network requirements and the presence of legacy users, allowing occupation of licensed bandwidth. To detect the vacant subcarriers, the cyclostationary detector is proposed, which allows to distinguish between spectrum holes, neighbor nodes radiation and the signals of licensed users.