First，the development trends of lunar communication，navigation and remote sensing（CNR）systems in the United States，Russia，Europe，Japan，and multilateral organizations were investigated，deriving insights for future development. Next， the current status of China’s lunar CNR system was analyzed and development needs from multiple perspectives，including supporting major engineering projects，enabling cis-lunar economic development，contributing to building China into a space power，safeguarding space assets，and promoting deep space international cooperation，were examined. It was proposed that China should accelerate the detailed design and key technology development of the Queqiao Communication，Navigation，and Remote Sensing Integrated Constellation System（QCNRSICS），actively advance international cooperation under Chinese leadership，and enhance its global standing. On this basis，a development concept for China’s QCNRSICS was proposed，covering construction objectives，overall architecture and development phases. Finally，nine critical technologies urgently requiring resolution for future constellation construction were identified.

To address the communication requirements among multiple spacecraft in Queqiao communication，navigation and remote sensing constellation system，and to tackle the challenges existing in deep space communication，such as long communication delays，frequent link interruptions and non-uniform protocols，an integrated cross-domain network topology architecture，consisting of ground networks，geostationary orbit networks，lunar surface networks，lunar orbit networks，planetary surface networks and planetary orbit networks，and a layered network protocol architecture integrating CCSDS，ECSS，and IETF protocol systems were proposed，achieving unified protocol configuration for inter-spacecraft，spacecraft-to-ground and intra-spacecraft communications. Simulation experiments of the cislunar space link have shown that the BP/LTP protocol achieved an effective throughput of over 90% in high-latency and high-packet-loss deep space communication environments，significantly outperforming TCP，QUIC and CFDP protocols. Finally，prospects for key technologies related to the integrated networking of constellation systems，such as architecture design and verification，network information services，high-reliability transmission and intelligent and efficient routing，were discussed. This study can provide technical support for future network system construction of the Queqiao communication，navigation and remote sensing constellation system and has significant engineering implications.

A cislunar relay cooperative transmission scheme was proposed based on the Queqiao communication，navigation，and remote sensing satellite constellation system. To address unreliable data transmission in ultra-long-distance cislunar communication environments caused by highly dynamic channels and significant path loss，using the in-orbit information processing and multi-source data fusion capabilities of Queqiao communication, navigation and remote sensing satellite constellation system. By introducing a symbol-level forwarding strategy and a multi-source redundancy sharing mechanism，a distributed RaptorQ transmission mechanism for heterogeneous data fusion was designed，enhancing the reliability of image data transmission. By adopting a block-based cyclic decoding algorithm，the computational complexity was reduced by 40% compared to the standard Gaussian elimination decoding algorithm，while still ensuring strong error correction performance. Simulation results demonstrate that in typical cislunar space communication scenarios，compared to traditional RS coding，the proposed distributed RaptorQ scheme achieved a 2 dB coding gain under equivalent coding redundancy. Compared to conventional relay storage-and-forward schemes，this approach increased decoding success rate by 20%，thereby improving image PSNR by over 5 dB，enabling highly reliable transmission of multi-source image data in cislunar space.

Based on the uplink of the Queqiao communication，navigation，and remote sensing constellation system，it is necessary to insert an Inter-Symbol Guard Time（ISGT）between Pulse Position Modulation（PPM）symbols to avoid the transmission of two consecutive pulses within an extremely short time interval. Based on the frame structure of M PPM + P ISGT and in the presence of signal blockage，an optical communication synchronization method based on timing offset estimation，namely the ISGT timing estimation method，has been proposed to address the issue of photon count detection utilizing the guard time in the existing frame format. This method effectively extracts the timing statistical information carried by the uplink optical signal frame structure，enabling slot synchronization for uplink optical signals. It avoids the additional consumption of data bandwidth caused by pilot signal synchronization while also mitigating or eliminating the impact of noise，such as Earth imagery and environmental stray light，on uplink optical signal synchronization. A joint simulation of this optical communication synchronization method was conducted，and the estimation results of the timing offset verify the feasibility of the ISGT timing estimation method. This approach can provide technical support for the Queqiao communication，navigation，and remote sensing constellation system.

To address key technical challenges of constellation design and high-precision orbit determination for the Lunar Communication and Navigation System（LCNS）an integrated orbit determination architecture which leverages multi-type orbital constellations and multi-source tracking resources from Earth，the Moon，and space was proposed. A hybrid constellation，comprising low lunar circular orbits，frozen elliptical orbits，and near-rectilinear Halo orbits，was designed based on lunar orbital dynamics to enhance coverage across global lunar surface and critical regions. For orbit determination，five observation modes were systematically compared and analyzed：Earth-based only，Moon-based only，Earth-based with inter-satellite，Moon-based with inter-satellite，and Earth-Moon-space joint modes. Their respective orbit determination accuracies were quantitatively evaluated. Simulation results demonstrate that the Earth-Moon-space joint mode substantially outperformed conventional approaches，improving accuracy from the meter level（in Earth-based only mode）to the centimeter level，thereby greatly enhancing navigation and positioning reliability for polar and far-side lunar missions. These findings provide theoretical support and engineering guidance for top-level constellation design，multi-mode orbit determination strategies，and the optimization of allocation resources allocation in future LCNS development.

The development status and trends of GNSS（Global Navigation Satellite System）cislunar navigation services，construction of lunar satellite navigation system，and lunar spatiotemporal benchmarks were analyzed in detail. A development concept for near Earth space，Earth-Lunar transfer，near Lunar space satellite navigation，and lunar spatiotemporal benchmarks was proposed. Additionally，suggestions are made about strengthening the research of key technologies and systematic in-orbit verification，achieving interconnectivity of cislunar satellite navigation system and unified traceability of spatiotemporal benchmarks，enhancing the integrated design of navigation and communication functions，and gradually establishing lunar space infrastructure in a “regional first，full Moon second” manner.

Due to the fact that the number of visible satellites is limited，the finiteness of observation information and the ill-condition of the observation equation seriously constrain the positioning accuracy of the Least Squares （LS） method. To address this，a spatiotemporal information-enhanced LS positioning optimization method for future Queqiao communication-navigation-remote sensing constellation was proposed，aiming to improve the robustness of LS-based solutions. First，an auxiliary equation incorporating multi-epoch pseudorange observations was constructed，coupled with a dynamic weighting strategy based on a constant-velocity motion model，to effectively utilize historical data and mitigate information deficiency in dynamic scenarios. Second，multi-epoch inter-satellite distance measurements are introduced to form geometric constraints that to suppress ill-conditioning in the observation model. Finally，a Forward-Backward Smoother （FBS） algorithm was applied to further refine positioning results and enhance solution stability. Simulation experiments based on platform-generated orbital data of the Queqiao constellation demonstrate that，under a 10 m orbital error and with a historical epoch length of 19，the proposed method—fusing multi-epoch pseudorange and inter-satellite distance data with FBS smoothing—achieved a positioning accuracy of 7.03 ± 2.50 m. Compared to the conventional LS method without any auxiliary information or smoothing，the positioning mean error was reduced by 88.26% and the standard deviation by 96.14%，providing solid technical support for high-precision positioning and navigation services required for Chinese astronauts’ lunar surface operations.

To address issues such as strong dependence on ground-based measurement and control in high-precision navigation of spacecraft in cislunar space，a high-precision navigation approach integratings X-ray pulsar and Queqiao constellation information. By coupling the X-ray pulsar observation data with the spacecraft ranging information provided by Queqiao Communication-Navigation-Remote Sensing constellation and incorporating cislunar orbital dynamics models，a joint navigation observation model of the Queqiao constellation and pulsars was constructed，and the navigation accuracy of the circumlunar orbit and the Earth-Moon L1 libration point Halo orbit was analyzed. Simulation results demonstrate that improvements of 90.11% and 88.73% in position accuracy for the two orbits have been achieved with the accuracy increasing from 1.73 km and 2.10 km to 187 m and 236 m compared with traditional X-ray pulsar navigation （XPNAV）. The joint navigation method proposed in this paper can significantly enhance the navigation and positioning performance，and provide theoretical reference and technical support for navigation applications in tasks such as cislunar space resource exploitation.

In response to the TT&C （Tracking，Telemetry，and Command） and communication needs of China's future lunar communication，navigation，and remote sensing integrated constellation serving users in Earth-Moon space，accuracy and applicability of various orbit determination technologies were comprehensively analyzed，including ground-based orbit determination，GNSS signal leakage orbit determination，BeiDou inter-satellite link orbit determination，LiAISON autonomous orbit determination，ground-assisted GNSS orbit determination，and lunar laser ranging orbit determination. The feasibility of communication methods for supporting the constellation，such as direct Earth-based Ka-band/laser communication and Ka-band/laser relayed communication was analyzed. Based on this，technical solutions are proposed to support the TT&C and communication of China's integrated constellation，providing technical support for the design and implementation of its TT&C system.

To address challenges such as ultra-large-scale spatial distribution，deep integration of heterogeneous services and quality-of-service management，an operational control and management architecture based on “Earth-Moon Collaborative-International Joint” was proposed. Core issues including significant ground-space control delay，multi-service resource competition and interoperability among international heterogeneous systems were tackled through an integrated functional framework incorporating constellation operation，network management，resource allocation，service provisioning and data governance，enabling full-lifecycle mission management through ground-based control，Earth-Moon coordination，and lunar-based response. On this basis，a five-layer technical architecture centered on“Acquisition-Capability-Support-Application-Service”was designed to facilitate flexible reuse and efficient integration of functional modules. This study offers architectural support for China’s future lunar and deep-space missions，provides a theoretical and engineering basis for efficient management of complex Earth-Moon constellation systems，and can help promote the development of intelligent，open and commercialized Earth-Moon space information infrastructure.

A multi-cluster collaborative cognition-based information system architecture was proposed from four aspects：overall architecture，hardware architecture，software architecture and protocol architecture，in response to Queqiao constellation system’s characteristics，such as super-large space-time scale，extreme spatial environment，and serious limitation of onboard resources，as well as the challenges of heterogeneous function fusion and resource collaborative scheduling，intelligent autonomous operation under intermittent link connection，and interconnection and elastic networking between satellites. With the perception-decision-execution loop at its center，it will effectively enhance cislunar space information interaction and intelligent collaboration capabilities，realize adaptive topology management，multi-source data fusion，and autonomous constellation system operation，and provide reference for the design of future constellation information systems.

The attitude and orbit control technologies for constellation systems were reviewed，focusing on aspects such as autonomous orbit determination，constellation configuration maintenance，high precision orbit control，attitude pointing control and angular momentum management. The technical challenges faced by the application of existing attitude and orbit control methods in the Queqiao CNRS were analyzed. The future research trends for attitude and orbit control technology were predicted，and suggestions were made for the development of components in attitude and orbit control systems，based on potential mission implementation requirements of constellation systems.

Against the backdrop of increasing space activities in the Earth-Moon space by countries worldwide and the continuous expansion of radio services，frequency resources are becoming increasingly strained.To face future demands，inherit existing frequency resources，consider new allocations，adapt to international competition and support international compatibility，frequency development trends were analyzed. It will provide support for a forward-looking top-level design for China’s deep space exploration.