Multi-Priority Based Interference Mitigation Scheme for HetNets Uplinks: A Frequency Hopping Method

Multi-tier interference is a critical issue in the HetNets uplinks, which dramatically deteriorates the system transmission performance and capacity. In this paper, we propose a prioritized radio-access scheme based on a frequency hopping (FH) technique to address the multi-tier interference issue. To endow the radio-access priorities to the users located at different tiers, a novel FH pattern (FH sequence set) with multi-level Hamming correlations are designed. As a study case, a low peak-to-average-power-ratio (PAPR) FH-based OFDM system (i.e, OFDMlFH system) employing the proposed FH sequence set is investigated in multi-tier HetNet uplinks. The performance in terms of anti-interference capability and spectral efficiency benefited from the proposed FH pattern are presented. The numerical and simulation results show that the proposed FH sequence set can provide a superior capability to mitigate the multi-tier interference in HetNet uplinks; meanwhile guarantee the transmission quality and the spectral efficiency for multi-tier users, even at the cell edge of HetNets.