A Bistatic ISAC Framework for LEO Satellite Systems: A Rate-Splitting Approach

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Park, Juha, Seong, Jaehyup, Ryu, Jaehak, Mao, Yijie, Shin, Wonjae
Format: Preprint
Veröffentlicht: 2024
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866913427858915328
author Park, Juha
Seong, Jaehyup
Ryu, Jaehak
Mao, Yijie
Shin, Wonjae
author_facet Park, Juha
Seong, Jaehyup
Ryu, Jaehak
Mao, Yijie
Shin, Wonjae
contents Aiming to achieve ubiquitous global connectivity and target detection on the same platform with improved spectral/energy efficiency and reduced onboard hardware cost, low Earth orbit (LEO) satellite systems capable of simultaneously performing communications and radar have attracted significant attention. Designing such a joint system should address not only the challenges of integrating two functions but also the unique propagation characteristics of the satellites. To overcome severe echo signal path loss due to the high altitude of the satellite, we put forth a bistatic integrated sensing and communication (ISAC) framework with a radar receiver separated from the satellite. For robust and effective interference management, we employ rate-splitting multiple access (RSMA), which splits and encodes users messages into private and common streams. We optimize the dual-functional precoders to maximize the minimum rate among all users while satisfying the Cramer-Rao bound (CRB) constraints. Given the challenge of acquiring instantaneous channel state information (iCSI) for LEO satellites, we exploit the geometrical and statistical characteristics of the satellite channel. To develop an efficient optimization algorithm, semidefinite relaxation (SDR), sequential rank-1 constraint relaxation (SROCR), and successive convex approximation (SCA) are utilized. Numerical results show that the proposed framework efficiently performs both communication and radar, demonstrating superior interference control capabilities. Furthermore, it is validated that the common stream plays three vital roles: i) beamforming towards the radar target, ii) interference management between communications and radar, and iii) interference management among communication users.
format Preprint
id arxiv_https___arxiv_org_abs_2407_08923
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle A Bistatic ISAC Framework for LEO Satellite Systems: A Rate-Splitting Approach
Park, Juha
Seong, Jaehyup
Ryu, Jaehak
Mao, Yijie
Shin, Wonjae
Information Theory
Networking and Internet Architecture
Aiming to achieve ubiquitous global connectivity and target detection on the same platform with improved spectral/energy efficiency and reduced onboard hardware cost, low Earth orbit (LEO) satellite systems capable of simultaneously performing communications and radar have attracted significant attention. Designing such a joint system should address not only the challenges of integrating two functions but also the unique propagation characteristics of the satellites. To overcome severe echo signal path loss due to the high altitude of the satellite, we put forth a bistatic integrated sensing and communication (ISAC) framework with a radar receiver separated from the satellite. For robust and effective interference management, we employ rate-splitting multiple access (RSMA), which splits and encodes users messages into private and common streams. We optimize the dual-functional precoders to maximize the minimum rate among all users while satisfying the Cramer-Rao bound (CRB) constraints. Given the challenge of acquiring instantaneous channel state information (iCSI) for LEO satellites, we exploit the geometrical and statistical characteristics of the satellite channel. To develop an efficient optimization algorithm, semidefinite relaxation (SDR), sequential rank-1 constraint relaxation (SROCR), and successive convex approximation (SCA) are utilized. Numerical results show that the proposed framework efficiently performs both communication and radar, demonstrating superior interference control capabilities. Furthermore, it is validated that the common stream plays three vital roles: i) beamforming towards the radar target, ii) interference management between communications and radar, and iii) interference management among communication users.
title A Bistatic ISAC Framework for LEO Satellite Systems: A Rate-Splitting Approach
topic Information Theory
Networking and Internet Architecture
url https://arxiv.org/abs/2407.08923