新一代GNSS星间链路导通融合信号模型研究

The construction of navigation constellation with inter-satellite links (ISLs) has become one of the important development trends for new generation global navigation satellite system (GNSS), and ISLs realize navigation and communication functions through low rate omnidirectional telemetry, tracking, & Command (TT&C) channel and high rate data service channel separately nowadays. If the above two functions are integrated on one channel, which means to simplify the equipment onboard, improve the electromagnetic compatibility, reduce power consumption and save frequency resources, so we can speculate that autonomous navigation will be achieved by ISLs with fusion of navigation and communication. The project mainly explores the signal fusion models of navigation and communication for ISLs, and proposes a signal fusion model of navigation and communication based on continuous phase modulation (CPM). The study involves many research areas, such as chaotic spread-spectrum, adaptive coded modulation, integration and separation of navigation and communication signals, Turbo detection principle, unambiguous acquisition and tracking, and so on. The accomplishment of this project not only establishes a design criteria for phase integration of ranging signal and communication signal, and uncovers the essential characteristics of joint non-binary channel coding and modulation scheme based on chaotic spread-spectrum sequences, but also perfects a comprehensive performance evaluation theory for compound signals, and enrichs signal detection mechanism of the receiver. The project also provides a new idea and feasible demonstration for BeiDou technological updating and next generation satellite signal structure design, and establishes the theoretic and technical foundation for the future development and applications in satellite navigation system.

建设有星间链路（ISLs）支持的导航星座已成为新一代全球导航卫星系统（GNSS）的主要发展趋势之一，目前星间链路通过低速率全向测控信道和高速率业务数据信道分别实现导航和通信，若将二者进行功能融合则可简化星上设备、提高电磁兼容能力、减少功率消耗、节约频率资源，可以推测未来星间链路将融合导航与通信功能并借此实现自主导航。本项目旨在探索适用于星间链路的导通融合信号模型，提出一种基于连续相位调制（CPM）的导通融合信号模型，内容涉及混沌测距、自适应编码调制、导通信号融合与分离、Turbo迭代检测以及无模糊捕获跟踪等多个领域的理论方法。该项目的完成可建立测距信号与通信信号相位复合的设计准则，揭示基于混沌序列的多元联合编码调制信号的本质特征，完善复合信号的质量评估理论，丰富接收机数据检测机制，为北斗导航系统的技术升级和下一代信号体制的设计提供新思路和可行性论证，并为其推广应用奠定理论和技术基础。

本项目基于新一代星地一体化卫星导航系统的管控架构，探索适用于星间链路的导通融合信号模型，提出了一种基于连续相位调制的导通融合信号模型，设计了能满足测距和通信需求的测距码序列与波形，建立了适用于GNSS星间链路的编码调制方案库，实现了测距信号和通信信号的融合与分离，评估了测距通信一体化信号的性能，确定了基于连续相位调制的导通一体化信号模型的实现方案。该项目的完成，可拓展卫星导航信号传输体制的设计方法，建立测距信号和通信信号的联合设计准则，丰富接收机信号检测机制，完善复合信号的质量评估理论，为北斗导航系统的技术升级和下一代信号体制的设计提供新思路和可行性论证。其研究成果还可广泛应用于其他远距离功率受限系统（如卫星通信、深空通信、遥测遥感、对潜通信、战术电台等），用以升级传输技术、改善传输机制、提高传输速率、降低接收机复杂度。