A Hybrid System and Technique for Sharing Multiple Spectrums of Satellite Plus Mobile Systems With Indoor Small Cells in 5G and Beyond Era

In this paper, we propose multiple communication systems incorporating an integrated satellite-mobile system (iSMS) and an autonomous terrestrial-mobile system (aTMS), and a technique to share multiple reused spectrum bands of iSMS and aTMS with in-building small cell base stations (SBSs) of aTMS by exploiting high external wall penetration loss of a building. The aTMS consists of a set of small cells enabled with either a single-band or multiband and deployed in a number of buildings. The iSMS consists of a satellite station integrated with the complementary ground components (CGC) stations which are deployed alongside small cells one-to-one basis. An interference management scheme to coordinate interference, a global resource scheduler to allocate resources, and an algorithm for the technique is proposed. We derive expressions for capacity, spectral efficiency, and energy efficiency under various SBS configurations for L buildings where L ≥ 1. An optimal value of L satisfying both energy and spectral efficiencies and an optimal number of almost blank subframes (ABSs) are derived. With extensive analysis, we show that the spectral efficiency improves linearly with the number of spectrum bands per SBS as well as L. However, the energy efficiency improves largely for low values o L and is hardly affected by the number of spectrum bands per SBS. An optimal value of L is obtained by choosing a slope on the energy efficiency curve for 0 ≤ L ≤ 100. The multiband enabled SBSs to provide with the best capacity, spectral efficiency, and energy efficiency performances of all SBS configurations. Furthermore, we show that the proposed technique outperforms several existing techniques in terms of energy efficiency, spectral efficiency, and average capacity per user equipment (UE) and can surpass the requirements of spectral and energy efficiencies for the fifth generation (5G) systems. Finally, we point out the significance, challenges, and future research perspectives of the proposed technique.