Modeling and coverage analysis of heterogeneous sub-6GHz-millimeter wave networks

The joint adoption of sub-6GHz and millimeter wave (mmWave) technology can prevent the blind spots of coverage, enabling comprehensive coverage while realizing high-speed communication rate. According to the sensitivity of mmWave, base stations should be more densely deployed, which is not well described by existing Poisson hole process (PHP) and the Poisson point process (PPP) models. This paper establishes a sub-6GHz and mmWave hybrid heterogeneous cellular network based on the modified Poisson hole process (MPHP). In our proposed model, the sub-6GHz base stations follow the PPP, and the mmWave base stations (MBSs) follow MPHP distribution. The expressions of the coverage probability are derived by using the interference calculation method of integrating the nearest sector exclusion area. Our theoretical analysis has been verified through simulation results, suggesting that the increase in the cell radius decreases the coverage probability of signal-to-interference-plus-noise ratio (SINR), whereas the increase in the sector parameter has the opposite effect. The variation of sub-6GHz base stations (SBSs) density imposes more significant impact than the MBSs on the SINR coverage probability. In addition, the decrease in MBSs density will reduce the average bandwidth allocated to the user equipment (UE), thus reducing the rate coverage probability.