Optimizing contention based access methods for FBMC waveforms

Filter Bank MultiCarrier modulation (FBMC) is a promising waveform technology envisaged for future mobile communication networks. For many transmission scenarios, the combination of multiple non-contiguous spectrum bands is foreseen. Because of coexistence issues, very low Adjacent Channel Leakage is required making FBMC waveforms of particular interest. However the fair frequency localization of FBMC results in a time spreading of the waveform: the filter impulse response introduces transitions which increase the duration of the burst with respect to classical multicarrier schemes such as Orthogonal Frequency Division Multiplexing and may reduce the overall spectral efficiency. In this work, we propose to study the performance of a FBMC waveform considering Carrier Sense Multiple Access with Collision Avoidance. Two mechanisms are employed for packet transmission: a basic access and a reservation scheme (based on RTS/CTS). We study how effective the RTS/CTS handshake is under ideal channel conditions by taking into account the specificities of the FBMC physical layer. Furthermore, we discuss about the RTS threshold value on packet size that maximizes throughput performance by employing one of both possible schemes and the impact of subchannel aggregation strategies on throughput and latency.