Abstract
This paper investigates a semi-grant-free (SGF) based transmission strategy to provide a flexible connectivity for various kinds of users in an integrated satellite-aerial-terrestrial network (ISATN). Herein, a high-altitude platform (HAP) termed as a grant-based user (GBU), which serves multiple mobile terminals (MTs) through space division multiple access (SDMA), wants to access a satellite network with multiple earth stations (ESs) termed as grant-free users (GFUs) simultaneously via non-orthogonal multiple access (NOMA) assisted SGF. To this end, we first propose two SGF-based uplink transmission schemes for both perfect channel state information (CSI) and imperfect CSI cases. When perfect CSI is available, a zero-forcing based beamforming (BF) scheme is used in HAP network while an adaptive transmit power allocation (ATPA) approach is adopted for SGF transmission. When only imperfect CSI is available, BF scheme employing the derived channel correlation matrix of HAP-MT link is proposed to achieve SDMA, and a novel ATPA strategy with rate probability constraint is proposed to guarantee quality-of-service of the GBU. Next, we derive the closed-form throughput expressions to evaluate the performance of the considered ISATN with the proposed two SGF-based schemes. Finally, computer simulations are conducted to validate the theoretical performance analysis and show the superiority of the proposed schemes over the related works. Moreover, our numerical results not only demonstrate a satisfactory performance of the proposed SGF-based scheme using imperfect CSI, but also reveal the impact of CSI errors on the system performance.
Original language | English (US) |
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Pages (from-to) | 1-1 |
Number of pages | 1 |
Journal | IEEE Journal on Selected Areas in Communications |
DOIs | |
State | Published - May 8 2023 |
Bibliographical note
KAUST Repository Item: Exported on 2023-05-12Acknowledgements: This work was supported by the Key International Cooperation Research Project under Grant 61720106003, NUPTSF under Grant NY220111, and the Postgraduate Research & Practice Innovation Program of Jiangsu Province under Grant KYCX21 0739.
ASJC Scopus subject areas
- Computer Networks and Communications
- Electrical and Electronic Engineering