Maximising spectral efficiency in 4th generation OFDM/TDMA TDD hybrid cellular mobile/ad-hoc wireless communications

A novel strategy is presented to maximise spectral-efficiency in 4^th generation OFDM/TDMA TDD wireless communications with 100% frequency re-use. This strategy involves permitting peer-to-peer communications at the edges of cells within the cellular mobile infrastructure and employing a novel medium-access-control protocol, denoted as channel-sensing TDMA TDD, to minimise intercellular interference and efficiently co-ordinate ad-hoc communication jointly. Channel-sensing TDMA TDD employs a modified busy-tone broadcast/channel-sensing mechanism to avoid and mitigate high interference scenarios. Results show significant improvements in system capacity and spectral-efficiency from the application of this novel approach compared to the state-of-the-art.