To achieve wide coverage in sixth-generation (6G) wireless communication systems, high-altitude platform stations (HAPSs) have received considerable research attention. Interference management is required between HAPSs and terrestrial networks to achieve high spectral efficiency in their coexisting environments. Some studies have proposed the combination of these systems with well-established multiple-input multiple-output (MIMO) techniques, forming a null toward each ground base station (BS). However, this approach is inadequate for protecting the entire ground cell, as a large-scale antenna can only form narrow nulls. The formation of multiple nulls around the ground BS could enhance the communication quality of the ground cell, but at the expense of the HAPS service area. To avoid this tradeoff, we propose a null-sweeping scheme, which dynamically handles the directions of nulls around ground BSs over time and/or frequency domains. By coordination between the HAPS and terrestrial systems, the scheme controls residual interference and improves the overall communication quality of ground cell users. The simulation results demonstrate that the proposed scheme significantly enhances the received signal-to-interference-plus-noise ratio (SINR) in the ground cells. Regardless of the spatial relationship between HAPS and ground cells, the proposed scheme can increase the sum capacity of the terrestrial systems by up to 15% without any quality degradation to HAPS users.
Spectrum Sharing Between High-Altitude Platforms and Terrestrial Networks Using Interference Coordination by Null Sweeping
10.10.2023
3436770 byte
Aufsatz (Konferenz)
Elektronische Ressource
Englisch