A relay satellite platform communication device for space-ground networking

Abstract

The application discloses a relay satellite platform communication device for networking between space and ground, belongs to the field of relay satellites, and is characterized in that the device is constructed by system-level integration of four core technologies, including a structure-electricity integrated central bearing frame, a plug-in modular system of 'one body and three surfaces', a conformal antenna integrated multifunctional shell and an internal-external collaborative heat pipe heat dissipation network, and a three-layer deep coupling architecture of'skeleton-module-skin' is constructed, six surfaces of the central bearing structure are divided into two areas of dynamic and static, which are a modularized enclosure area and a fixed function area respectively, the dynamic area is used for realizing function reconfiguration and on-orbit maintenance, and the static area is used for deploying a high-reliability platform basic system which is fixed and unchanged once launched. The application solves the problems of on-orbit maintenance difficulty, low reliability and performance bottleneck caused by the architecture dispersion and function coupling of traditional relay satellites, and provides a satellite platform foundation with high reliability, high flexibility and easy maintenance for constructing a dynamic reconfigurable space-ground integrated information network.

Description

Technical Field

[0001] This invention belongs to the field of relay satellite platforms, and specifically relates to a relay satellite platform communication device for space-ground networking. Background Technology

[0002] As a crucial component of the national information infrastructure, the integrated space-ground information network is undergoing a critical phase from proof-of-concept to practical deployment. With the rapid development of emerging technologies such as 5G / 6G communication, low-Earth orbit satellite constellations, and space-based internet, traditional relay satellite systems face the dual challenges of architectural innovation and performance upgrades. At the macro level, a global effort is accelerating the construction of a comprehensive communication network covering space, air, ground, and sea, placing higher technical demands on relay satellites as space-based information hubs. According to predictions from the International Telecommunication Union (ITU) and several space agencies, by 2030, the number of satellites in orbit globally will exceed 50,000, most of which will require relay satellites to maintain continuous connectivity with the ground.

[0003] At the technological development level, modern space missions are characterized by diversification and dynamism. Low-Earth orbit remote sensing satellites require the real-time transmission of massive amounts of observational data, manned space missions demand reliable space-to-ground communication, and commercial constellation operations require flexible bandwidth allocation capabilities. All of these place new demands on the capacity, flexibility, and reliability of relay satellite systems. Simultaneously, with the application of new technologies such as software-defined radio, optical communication, and artificial intelligence in the aerospace field, relay satellite systems are facing a technological inflection point, transitioning from traditional fixed functions to intelligent reconfigurability.

[0004] Within the existing technological framework, modular satellite design has developed into several representative technical routes. The CubeSat standard, as the most mature modular solution, has evolved into a complete system ranging from 1U to 27U, and its standardized mechanical interfaces and electrical specifications have provided the basic framework for hundreds of satellite projects worldwide. NASA's PhoneSat project further validated the feasibility of building satellite systems using commercial smartphone components, promoting the application of modular design in the low-cost satellite field.

[0005] Regarding higher-performance satellite platforms, the European Space Agency (ESA) has developed a standardized satellite platform with a modular design, separating the service module and payload module for rapid integration via standard interfaces. This design approach has been successfully validated on the Sentinel series of Earth observation satellites. Meanwhile, DARPA's "Space Systems Enabling Technologies" program explores a modular architecture based on standard electronic units, aiming to enable rapid replacement and upgrades of satellite components.

[0006] In the commercial space sector, SpaceX's Starlink satellites employ a highly integrated modular design, enabling rapid deployment through mass production and standardized interfaces. The system's phased array antennas and propulsion modules also utilize a modular design concept, supporting on-orbit functional reconfiguration. Planet Labs' Skysat series satellites, on the other hand, achieve flexible configuration of remote sensing payloads through standardized camera modules and platform interfaces.

[0007] In the field of specialized communications satellites, Airbus' Eurostar Neo platform employs a "plug-and-play" payload interface standard, allowing customers to select different communication payloads as needed. Boeing's 702X platform also adopts a similar modular design concept, supporting multiple mission configurations through standardized power and data interfaces.

[0008] Furthermore, in the field of academic research, MIT's "self-assembling satellites" concept explores autonomous assembly technology based on smart connectors, providing new ideas for future on-orbit reconfiguration. Stanford University's Space Systems Development Laboratory is dedicated to developing modular communication systems based on software-defined radio, supporting on-orbit software updates and functional reconfiguration.

[0009] These existing technological solutions have promoted the development of satellite modularization at different levels, from the mechanical standardization of CubeSats to the platform modularization of commercial satellites, and then to the standardization of payload interfaces for communication satellites, forming a multi-level accumulation of technology and laying a solid foundation for the innovation of the next generation of relay satellite systems.

[0010] Existing relay satellite technology has the following specific technical shortcomings when applied to integrated space-ground networking applications:

[0011] In terms of interface design, existing modular solutions cannot meet the actual needs of on-orbit maintenance of relay satellites. Taking the current mainstream CubeSat standard as an example, after experiencing the severe vibrations during launch and the thermal cycling of the space environment, the contact resistance of its connectors increases significantly, leading to unstable power supply and degraded signal quality. More importantly, existing connectors lack a precise guiding and positioning mechanism, failing to support the precise docking requirements of robotic arm operations on orbit. The purpose of this invention is to solve this specific problem by designing a blind-mating connector with a triple guiding structure, completing the initial positioning of the electrical connection before mechanical contact, ensuring a high success rate for on-orbit replacements.

[0012] In terms of system integration, existing relay satellites still use point-to-point cable connections between their internal subsystems. Taking a certain type of relay satellite in orbit as an example, its internal cable length exceeds 300 meters, with over 2000 connection points. This design not only increases system weight but also makes it difficult to guarantee signal integrity. This invention specifically embeds a multi-layer electronic backplane as the "core material" within the carbon fiber main load-bearing structure, creating an integrated load-bearing body where "structure is the backplane." This completely eliminates internal cable bundles and the vast majority of independent electrical connectors, thereby significantly reducing the number of connection points, lowering system weight, shortening signal paths, and improving signal integrity and inherent system reliability.

[0013] In terms of thermal management, existing modular designs often neglect the heat dissipation requirements of high-power modules. For example, a certain commercial communication module has a heat density of 15W / cm² when operating at full power, while existing heat dissipation solutions can only provide a heat dissipation capacity of 8W / cm², forcing the module to be derated. This invention innovatively integrates the thermal management system with the mechanical structure, using embedded heat pipes to increase the heat dissipation capacity to 20W / cm², ensuring that all modules can operate stably at full power. Summary of the Invention

[0014] To address the aforementioned problems, this invention provides a relay satellite platform communication device for space-ground networking, aiming to solve the docking difficulties of on-orbit replacement, eliminate internal cable connections, improve signal transmission quality, increase space utilization, and ensure the heat dissipation requirements of high-power modules. The technical solution adopted is as follows:

[0015] A relay satellite platform communication device for space-ground networking includes a central support structure. The central support structure has a cubic frame. Of the six faces formed by the cubic frame, except for one side, the other five faces are provided with carbon fiber laminates to form a semi-enclosed structure. A back plate is fixed to the inner surface of the carbon fiber laminate.

[0016] The backplane has a layered architecture. When the backplane is placed horizontally, the layers from top to bottom are: ground layer, control layer, signal layer, power layer, signal layer, control layer, and ground layer.

[0017] The central load-bearing structure houses a platform-level core unit within its cavity, which requires no on-orbit replacement or has specific installation requirements. The central load-bearing structure is externally enclosed by a multi-functional platform shell.

[0018] The six sides of the central load-bearing structure are divided into two areas: a modular enclosure area and a fixed functional area. The modular enclosure area includes the top carbon fiber laminate, the first side carbon fiber laminate, and the second side carbon fiber laminate of the central load-bearing structure. The remaining three sides of the central load-bearing structure are the platform fixed functional areas.

[0019] The modular enclosure contains management, computing, and communication modules. The fixed functional area of ​​the platform is used to deploy the basic systems that remain unchanged after launch.

[0020] The multi-functional platform shell is a cube composed of six protective plates made of carbon fiber composite material. The laser communication terminal antenna is installed in the center of the top protective plate. A Ku-band parabolic antenna is set on the surface of the first protective plate. The second and fourth protective plates adopt microstrip patch array technology to directly fabricate the 64 radiating elements of the Ka-band phased array antenna on the surface circuit of the protective plate in an array form.

[0021] The backplate is embedded with microchannel heat pipes, which utilize a sintered copper powder capillary structure. Each microchannel heat pipe has an evaporation section that is in close contact with the carbon fiber laminate, rapidly absorbing heat transferred from the modules to the carbon fiber laminate. The inner surface of the protective plate is equipped with heat dissipation pipes that cover the plate. These heat dissipation pipes have condensation sections that make large-area contact with the protective plate. The condensation and evaporation sections are connected via heat pipe manifold connectors located at the junction of the central support structure and the multi-functional platform.

[0022] Furthermore, the aforementioned relay satellite platform communication device for space-ground networking is further provided with multiple standard slots and communication function modules on the first side carbon fiber laminate. The standard size of the communication function module is 300×200×150 mm. The communication function module includes an inter-satellite link module responsible for high-speed inter-satellite data transmission and a satellite-to-ground relay module responsible for satellite-to-ground communication.

[0023] The second carbon fiber laminate has multiple standard slots for installing computing modules. The standard size of the computing modules is 250×200×100 mm. The computing modules include a network switching module responsible for data routing and an FPGA-based dynamic resource scheduling module responsible for dynamic resource allocation.

[0024] The top carbon fiber laminate has multiple standard slots for installing management function modules. The standard size of the management function modules is 300×200×200 mm. They integrate the platform's power control, lithium-ion battery pack, space computer, and thermal control unit, forming the platform's energy, information, and control hub.

[0025] Furthermore, the aforementioned relay satellite platform communication device for space-ground networking further eliminates the need for on-orbit replacement or special requirements for installation location. The platform-level core units include propellant tanks and their piping systems, high-precision inertial reference units, the most basic core firmware, and platform safety control computers.

[0026] Furthermore, in the aforementioned relay satellite platform communication device for space-ground networking, a management function module is installed on the top carbon fiber laminate of the central supporting structure, a computing function module is installed on the first carbon fiber laminate, and a communication function module is installed on the second carbon fiber laminate.

[0027] Furthermore, the aforementioned relay satellite platform communication device for space-ground networking further features a backplane made of FR-4 substrate with a total thickness of 2.4 mm. The backplane has a 12-layer internal structure, consisting of a grounding layer, a control layer, two signal layers, four power layers, two signal layers, a control layer, and a grounding layer, from top to bottom.

[0028] Furthermore, the aforementioned relay satellite platform communication device for space-ground networking further features an optical window protected by high-strength sapphire glass, an operating wavelength of 1550nm, a communication rate of up to 10Gbps, a Ku-band parabolic antenna located at the center of the first side panel and integrated with the first side panel, and an operating frequency covering 12-18GHz.

[0029] Furthermore, the aforementioned relay satellite platform communication device for space-ground networking further includes a gradient CTE transition layer between the backplate and the carbon fiber laminate.

[0030] Furthermore, the aforementioned relay satellite platform communication device for space-ground networking further includes an inter-satellite link module that integrates a laser communication terminal and a Ka-band phased array radio frequency front-end, and a satellite-to-ground relay module that integrates a Ku / Ka band transceiver and processing unit.

[0031] Furthermore, in the aforementioned relay satellite platform communication device for space-ground networking, the module is inserted into a standard slot. Guide rails are provided on both sides inside the standard slot, and sliders that cooperate with the guide rails are provided on both sides of the module insertion end. The two sides of the module insertion end gradually contract inward to form an inclined surface with a guiding function. After the module is fully connected to the standard slot, the floating blind-mating connector at the bottom of the module provides ±0.5mm floating compensation to ensure that 240 pins can make contact evenly at the same time. Subsequently, the mechanical locking device at the top of the module is activated to apply a constant locking force of 20N.

[0032] Furthermore, the aforementioned relay satellite platform communication device for space-ground networking further incorporates a four-layer power supply layer using 2oz copper foil to distribute a 28V primary power supply and a 100V high-voltage bus, with a maximum transmission power of 3000W, and integrates overcurrent and overvoltage protection functions.

[0033] The four signal layers are dedicated to transmitting SpaceWire high-speed differential signals, with characteristic impedance controlled at 100Ω±10% and a transmission rate of no less than 200Mbps. This signal layer adopts a stripline design and is electromagnetically shielded by a ground layer.

[0034] The two control layers are equipped with a CAN bus network with a transmission rate of 1Mbps, which is used for platform health management and command telemetry transmission.

[0035] Two grounding layers provide a complete reference ground plane and power return path.

[0036] This invention integrates four core technologies at the system level: a structural-electrical integrated central support frame, a "one-body, three-sided" pluggable modular system, a conformal antenna integrated multifunctional shell, and an internally and externally coordinated heat pipe cooling network. It constructs a three-layer deeply coupled system architecture of "skeleton-module-skin", which aims to solve the problems of difficult on-orbit maintenance, low reliability, and performance bottlenecks caused by the discrete architecture and functional coupling of traditional relay satellites. It provides a highly reliable, flexible, and easy-to-maintain satellite platform foundation for building a dynamically reconfigurable space-ground integrated information network.

[0037] The beneficial effects of this invention are:

[0038] 1. Breakthrough improvement in on-orbit maintenance capabilities

[0039] Compared to the connectors used in CubeSat standard systems and the compartmentalized design of ESA standardized platforms, the three-level guided blind-mating interface system proposed in this invention solves the technical challenge of precise on-orbit docking. Through the synergistic effect of the coarse guide cone surface, precision guide rail, and floating connector, the docking success rate is increased from less than 90% to over 99.9%, and the contact resistance is stabilized below 3.2mΩ, achieving true on-orbit "hot-swap" functionality.

[0040] 2. A qualitative leap has been achieved in system integration.

[0041] Compared to the modular design of SpaceX Starlink satellites and the "plug-and-play" interface of the Airbus Eurostar Neo platform, this invention reduces the number of internal connection points from more than 2,000 to 96 through structural-electrical integrated design, significantly reduces the total cable length from more than 300 meters, and reduces the dry weight of the system by 18%.

[0042] 3. Significantly enhanced thermal management performance

[0043] To address the issue that existing modular designs cannot meet the heat dissipation requirements of high-power modules, this invention employs a thermal-structural synergistic design. Microchannel heat pipes are embedded within the carbon fiber shell and on the surface of the multi-layer integrated electronic backplane of the central load-bearing structure, increasing the heat dissipation capacity from 8W / cm² to 20W / cm². This ensures stable full-power operation of high-power modules such as Ku-band power amplifiers, with module temperatures controlled below 85℃.

[0044] 5. Overall improvement in system reliability

[0045] Compared to the connection reliability issues of existing modular solutions, the integrated design of this invention reduces potential system failure points by 96%. Combined with a high-reliability interface design, it increases the system mean time between failures (MTBF) from 85,000 hours to 150,000 hours and shortens on-orbit maintenance time from 3-5 days to less than 4 hours.

[0046] 6. Electromagnetic compatibility perfectly resolved.

[0047] Through innovative designs such as layered layout, electromagnetic isolation bulkheads, and backplate stripline structure, the electromagnetic interference problem in the integration of multi-band communication systems has been effectively solved, suppressing in-band interference from -35dB to below -65dB, and achieving harmonious coexistence of laser, Ka, and Ku multi-band communication systems. Attached Figure Description

[0048] Figure 1 This is a schematic diagram of the structure of the present invention. The diagram only shows details of one side carbon fiber laminate, one side guard plate, and the top carbon fiber laminate.

[0049] Figure 2 Schematic diagram of the back panel cross section;

[0050] Figure 3 This is a schematic diagram of the module docking process with the standard slot, where a is the coarse guiding stage, b is the precision guiding stage, and c is the connection locking stage.

[0051] Among them, 1-carbon fiber laminate, 2-grounding layer, 3-control layer, 4-signal layer, 5-power layer, 6-protective plate, 9-laser communication terminal antenna, 10-64 radiating units, 11-microchannel heat pipe, 12-heat pipe, 13-heat pipe busbar connector, 14-installation management function module, 15-standard slot, 16-guide rail, 17-slider, 18-floating blind mating connector, 19-mechanical locking device, 20-central load-bearing structure. Detailed Implementation

[0052] The present invention will be described in detail with reference to specific embodiments.

[0053] like Figure 1 The illustrated relay satellite platform communication device for space-ground networking adopts a modular frame design, including a central load-bearing structure. Its basic skeleton is formed by connecting carbon fiber composite rods at nodes, creating a cubic frame with external dimensions of 1500mm × 1500mm × 800mm. All twelve sides of the cubic frame are composed of carbon fiber composite rods with rectangular cross-sections of 50mm × 30mm. Of the six faces of the cubic frame, except for one side, the other five faces are fitted with carbon fiber laminates, forming a semi-enclosed structure. A backplate (not shown) is fixed to the inner surface of the carbon fiber laminate. Figure 1(As shown in the figure). The cavity of the central load-bearing structure houses a platform-level core unit (not shown in the figure) that does not require on-orbit replacement or has special requirements for installation location. The central load-bearing structure is surrounded by a multi-functional platform shell.

[0054] The six outer surfaces of the central load-bearing structure are clearly divided into two areas with different functions and maintenance characteristics: the modular maintenance area ("dynamic" area) and the platform fixed function area ("static" area).

[0055] The modular maintenance area (“dynamic” area) is the core of the platform's ability to achieve functional reconfiguration and on-orbit maintenance. The modular enclosure area includes the top carbon fiber laminate of the central load-bearing structure and the first and second side carbon fiber laminates. The first, second, and third side carbon fiber laminates are named sequentially according to their order.

[0056] The first side carbon fiber laminate has six standard slots for installing computing modules. The standard dimensions of the computing modules are 250×200×100mm, and they include a network switching module responsible for data routing and an FPGA-based dynamic resource scheduling module responsible for dynamic resource allocation. The number of modules can be defined according to different requirements.

[0057] The second side carbon fiber laminate has eight standard slots for installing communication function modules. The standard dimensions of the communication function modules are 300×200×150mm, and they specifically include an inter-satellite link module (integrating a laser communication terminal and a Ka-band phased array RF front-end) responsible for high-speed inter-satellite data transmission and a satellite-to-ground relay module (integrating a Ku / Ka-band transceiver and processing unit) responsible for satellite-to-ground communication. The number of modules can be defined according to different requirements.

[0058] The top carbon fiber laminate has four standard slots for installing management function modules (only two standard slots and two management function modules are shown in the diagram). The standard dimensions of the management function modules are 300×200×200mm. They highly integrate the platform's power control, lithium-ion battery pack, spaceborne computer, and thermal control unit, forming the platform's energy, information, and control hub. The number of modules can be defined according to different needs.

[0059] The platform's fixed functional area ("static" zone) is used to deploy a highly reliable platform foundation system that remains stationary once launched. A large heat sink is located on the fourth side carbon fiber laminate. The third side of the central load-bearing structure does not have a carbon fiber laminate. Platform-level core units are pushed into the central load-bearing structure through the third side, and these core units are fixed to the bottom carbon fiber laminate. This partitioning design ensures the stability of the platform foundation services and complements the maintainability of the "dynamic" zone.

[0060] like Figure 2As shown, the backplane uses FR-4 backplane substrate with a total thickness of 2.4mm. It has a 12-layer high-density circuit structure. When the backplane is placed horizontally, it consists of a ground layer, a control layer, two signal layers, four power layers, two signal layers, a control layer, and a ground layer from top to bottom.

[0061] The system comprises four power layers using 2oz copper foil to distribute the 28V primary power and 100V high-voltage bus, with a maximum transmission power of 3000W and integrated overcurrent and overvoltage protection. Four signal layers are dedicated to transmitting SpaceWire high-speed differential signals, with a characteristic impedance controlled at 100Ω±10% and a transmission rate of no less than 200Mbps. This signal layer uses a stripline design and is electromagnetically shielded by a grounding layer. Two control layers deploy a CAN bus network with a transmission rate of 1Mbps for platform health management and command telemetry transmission. Two grounding layers provide a complete reference ground plane and power return path. To overcome the thermal expansion coefficient mismatch between the carbon fiber laminate and the FR-4 backplane substrate, a gradient CTE transition layer is placed between them during the lamination process. This transition layer consists of copper-Invar-copper composite foil and modified epoxy resin. The lamination curing process parameters are: a heating rate of 2℃ / min and a holding time of 120 minutes at 180℃±5℃.

[0062] The internal cavity of the central load-bearing structure is used to install high-reliability platform-level core units that do not require on-orbit replacement or have special requirements for installation location:

[0063] (1) Propellant tanks and their piping systems.

[0064] (2) High-precision inertial reference unit (IRU) is installed at the platform's core to reduce disturbances.

[0065] (3) The most basic core firmware and platform security control computer.

[0066] The backplanes of each area are electrically interconnected through pre-installed jumper circuits within the frame, thus forming a complete distributed electronic backplane system. This design allows the structural panel of each functional surface to simultaneously serve as the support and carrier of the electronic system in that area, achieving true structural-electrical integration.

[0067] The multi-functional platform shell is a cube composed of six protective plates made of carbon fiber composite material. A laser communication terminal antenna is mounted at the center of the top protective plate, with its optical window protected by high-strength sapphire glass. It operates at a wavelength of 1550nm and achieves a communication rate of up to 10Gbps. The first side protective plate integrates a Ku-band parabolic antenna via an embedded recess, conforming the antenna aperture to the curved surface of the protective plate. It operates in the 12-18GHz frequency range and also serves as the ground plane for this parabolic antenna. The second and fourth side protective plates utilize microstrip patch array technology, directly fabricating the 64 radiating elements of a Ka-band phased array antenna onto the surface circuitry of the protective plate. This design makes the protective plate itself both the antenna's supporting structure and its radiators and ground plane, operating in the 26.5-40GHz frequency range. The carbon fiber composite shell thus serves three core functions: part of the main load-bearing structure, the grounding and radiating element for the conformal antenna, and the final thermal radiating surface for the platform's thermal management system. Its outer surface undergoes anodizing treatment to form a highly efficient radiation coating with a thermal emissivity of 0.85. The multifunctional platform shell is not only the main load-bearing structure and physical protective layer of the platform, but also integrates thermal control radiation and multi-band communication antenna functions through integrated design, becoming the final carrier of the "structure-thermal control-communication" triple function integration.

[0068] This invention addresses the potential electromagnetic interference problem arising from the integration of multi-band antennas in a compact space by employing a comprehensive design:

[0069] (1) Spatial isolation and partitioned layout: Antennas operating in different frequency bands (optical, Ku, Ka) are arranged on different planes of the platform, and natural isolation is achieved by utilizing physical distance and the shielding effect of the structure itself.

[0070] (2) Transmission channel integrity guarantee: In the design of the electronic backplane embedded in the central bearing structure, high-speed signal lines are arranged in the inner layer and strictly adopt the stripline structure. The upper and lower grounding layers are used to achieve shielding, effectively suppressing crosstalk between signals.

[0071] To address the heat dissipation challenges of high-power modules and fully utilize the platform's structural characteristics, this invention constructs a low-thermal-resistance, coordinated internal and external heat dissipation system that runs through the entire structure from module to backplane to frame to outer shell. This system comprises a distributed heat pipe network and a high-emissivity outer shell, achieving efficient heat collection, transfer, and dissipation.

[0072] The heat dissipation system mainly consists of two physically separate but functionally coupled heat pipe networks:

[0073] (1) Internal heat conduction network (located in the central load-bearing structure):

[0074] At the heart of this network is an embedded microchannel heat pipe. This heat pipe employs a sintered copper powder capillary structure with an equivalent thermal conductivity as high as 12000 W / (m·K). These pipes are meanderingly arranged and embedded within a carbon fiber laminate, with the evaporation section closely attached to the laminate. Its primary function is to rapidly absorb heat conducted from the heating module to the backplate via a blind-plug interface, and to efficiently conduct and even out heat within the entire central load-bearing structural frame, preventing the formation of localized "hot spots" at the module mounting location. The heat generated during module operation is directly conducted through the backplate to the wall of this contacting section of the heat pipe, causing the working fluid inside to absorb heat and evaporate. This section of the heat pipe is thus defined as the evaporation section.

[0075] (2) External heat dissipation network (located on the platform shell):

[0076] This network consists of main heat pipes attached to the inner surface of the multi-functional platform's outer shell. This heat pipe network covers the inner wall of the shell, with its condensation section in large contact with the inner surface. The shell itself serves as the system's final heat radiation surface; its carbon fiber composite outer surface is anodized and has a high thermal emissivity coating of no less than 0.85.

[0077] The internal heat conduction network and the external heat dissipation network do not operate independently. At the connection boundary between the central load-bearing structure and the multi-functional platform shell, they are mechanically and thermally linked through a specially designed heat pipe manifold connector. Specifically, at this node, the ends of each heat pipe in the internal heat conduction network (condensation functional section) and the corresponding ends of the heat pipes in the external heat dissipation network (evaporation functional section) achieve low thermal resistance coupling through welding or interference fit of a high thermal conductivity metal (copper or aluminum), thus constructing a continuous low thermal resistance path from the module mounting surface to the shell's radiating surface. In the section where the heat pipe contacts the inner wall of the shell, the working fluid inside the pipe releases heat to the relatively low-temperature shell and condenses; this part of the heat pipe is thus defined as the condensation functional section.

[0078] The heat dissipation process follows this path:

[0079] (1) Heat collection and initial diffusion: The heat generated by the heating module is directly conducted to the carbon fiber laminate back plate of the corresponding mounting surface through the metal shell and blind-mating connector at its bottom.

[0080] (2) Internal lateral heat transfer and temperature equalization: The heat on the back plate is rapidly diffused by the integrated thick copper foil power layer and dedicated heat-conducting strip, and then absorbed by the internal heat-conducting network (embedded heat pipe) directly below it. The heat pipe efficiently transfers heat from the local heat source to the entire structural frame through the phase change cycle of the working fluid, achieving initial temperature equalization.

[0081] (3) Internal and external heat flow convergence and conduction: The heat gathered in the structural frame is efficiently transferred to the external heat dissipation network (outer shell heat pipe) through the heat pipe convergence connector.

[0082] (4) Final radiative heat dissipation: The external heat dissipation network rapidly conducts heat to the entire multi-functional platform shell. With its large surface area and high thermal emissivity (0.85), the shell effectively dissipates heat in the form of thermal radiation to the space environment with a temperature of approximately 3K, completing the entire heat dissipation cycle.

[0083] Through the structured thermal path design described above, this collaborative heat dissipation system achieves a total thermal resistance of only 0.48°C / W from the module's heat source node to the space environment. This low thermal resistance enables the system to handle heat dissipation up to 20W / cm² heat density, ensuring that even under the most severe operating conditions, the core junction temperature of the high-power module is stably controlled below the safe threshold of 85°C, thereby guaranteeing the long-term reliable operation of the platform's electronic equipment at full power.

[0084] like Figure 3 As shown, guide rails are provided on both sides inside the standard slot, and the module is inserted into the standard slot. The two sides of the module insertion end gradually taper inward to form an inclined surface with a guiding function, entering the coarse guiding stage, achieving initial macro-motion tolerance capture of ±5mm, and guiding the module smoothly into the slot.

[0085] The module insertion end has sliders on both sides that cooperate with the guide rails. After the module is initially aligned with the standard slot, it enters the precision guiding stage. The precision guide rails on both sides of the slot engage with the corresponding sliders on the side of the module, and the alignment accuracy is controlled within ±0.05mm in the last 10mm stroke, thus completing the fine alignment.

[0086] After the module is fully mated with the standard slot, the connection locking phase begins. The floating blind-mating connector at the bottom of the module provides ±0.5mm of floating compensation, ensuring that all 240 pins make simultaneous and uniform contact. Subsequently, the mechanical locking device at the top is activated, applying a constant locking force of 20N, ultimately achieving mechanical fixation of the module and stable electrical connection. This design ensures that the electrical connection maintains extremely high reliability even under vibration and shock environments and after repeated mating and unmating. The floating blind-mating connector is a Nano-D type high-density blind-mating connector conforming to the MIL-DTL-32139 standard, and the mechanical locking device is a quarter-turn quick-lock mechanism.

[0087] The three-level guide interface mechanism of each module slot is directly led out from the electronic backplane pre-embedded in the corresponding surface structure, realizing the "plug and play" of the module and fundamentally eliminating the complex cable interconnection inside the satellite.

[0088] This integrated design, by embedding the electronic backplane within the load-bearing structure, physically creates an electrical interconnection network centered on the backplane. This fundamental change replaces the long, discrete bundles of cables between traditional satellite modules with precision transmission lines integrated within the backplane, directly reducing the number of connection points from over 2,000 to 96 standardized blind-mating interfaces and significantly shortening the high-speed signal transmission path. The extensive elimination of connectors, cables, and auxiliary supports directly results in an 18% reduction in system dry weight. Simultaneously, because signals are transmitted through striplines laminated to the backplane with strictly controllable impedance, impedance mismatch and signal attenuation caused by long cables are avoided, fundamentally improving signal integrity.

[0089] In realizing this invention, the following three key technical challenges were mainly overcome from the perspective of core structural design:

[0090] (1) The challenge of integrated co-curing molding of distributed backsheet and main load-bearing frame

[0091] Traditional satellite structures only serve a mechanical load-bearing function, with electronic systems mounted as independent components. The core structural challenge of this invention lies in integrating a functionally independent, 12-layer FR-4 printed circuit board (backplane) as a structural "core material" with carbon fiber laminates on the +X, +Y, and +Z mounting surfaces through integrated co-curing. This not only requires the backplane itself to maintain structural integrity and electrical stability during the high-temperature, high-pressure curing of the composite material, but also necessitates addressing residual stress control at the interface of large-sized heterogeneous materials (carbon fiber composite and FR-4) and the risk of delamination under long-term thermal cycling. This invention achieves reliable fusion of heterogeneous materials at the structural level by customizing a gradient coefficient of thermal expansion (CTE) transition layer for each backplane interface and optimizing the curing process, transforming the electronic backplane from an "mounting component" into a "structural component."

[0092] (2) Design challenges of modular slot structure to support precise on-orbit guidance and locking

[0093] The "one-body, three-sided" architecture requires the structure itself to provide a high-precision, highly reliable mechanical guide and locking foundation for the modules. The challenge lies in how to directly construct a composite slot structure on the main load-bearing frame capable of accommodating a three-stage guiding mechanism (coarse guide cone, precision guide rail, and floating connector). This demands that the frame possess extremely high local stiffness, dimensional stability, and wear resistance at corresponding locations to withstand the mechanical wear of repeated insertions and removals, and ensure that deformation during module locking (with a 20N locking force) remains within micrometer-level tolerances. This invention addresses this by implementing local reinforcement design at key nodes of the carbon fiber rod frame and pre-embedding high-precision metal guide rail inserts, making the load-bearing structure itself the base for the high-precision interface.

[0094] (3) The challenge of integrating thermal management functions with the main load-bearing structure

[0095] To achieve efficient heat dissipation, the heat pipe network needs to be deeply embedded in the main load-bearing structure, which brings new structural challenges. Challenge 1: How to embed microchannel heat pipes within the carbon fiber rods and ensure good thermal contact without significantly weakening their mechanical properties. Challenge 2: How to achieve reliable, low thermal resistance coupling between the internal (frame) and external (shell) heat pipe networks at the structural boundary, while ensuring this coupling node can withstand launch vibrations and on-orbit thermal stress. This invention addresses this by pre-reserving heat pipe channels during rod layering and providing local reinforcement, as well as designing dedicated metal manifold connectors with thermal compensation capabilities, thus creating an integrated, skeletal structure that connects the heat dissipation system and the load-bearing structure.

Claims

1. A relay satellite platform communication device for space-ground networking, characterized in that, The center bearing structure includes a cubic frame, and carbon fiber laminates are arranged on five of the six surfaces of the cubic frame to form a semi-closed structure, and a backboard is fixed to the inner surface of the carbon fiber laminates; The backboard has a layered structure, and when the backboard is placed horizontally, the layers are arranged in order from top to bottom as a grounding layer, a control layer, a signal layer, a power supply layer, a signal layer, a control layer, and a grounding layer; A platform-level core unit that does not need to be replaced on the track or have special requirements for the installation position is arranged in the cavity of the center bearing structure, and a multifunctional platform shell is arranged outside the center bearing structure; The six surfaces of the center bearing structure are divided into two areas, namely a modular enclosure area and a fixed function area, the modular enclosure area includes the top carbon fiber laminate, the first side carbon fiber laminate, and the second side carbon fiber laminate of the center bearing structure, and the remaining three surfaces of the center bearing structure are the platform fixed function area; The modular enclosure area is provided with a management function module, a computing function module, and a communication function module, and the platform fixed function area is used to deploy a basic system that is fixed after being launched; The multifunctional platform shell is a cubic structure composed of six panels, the panels are made of carbon fiber composite materials, a laser communication terminal antenna is arranged at the center of the top panel, a Ku-band parabolic antenna is arranged on the surface of the first side panel, and the second side panel and the fourth side panel adopt a microstrip patch array technology to directly manufacture 64 radiation units of a Ka-band phased array antenna on the surface circuit of the panel in an array form; Micro-channel heat pipes are embedded in the backboard, the micro-channel heat pipes adopt a sintered copper powder capillary structure, the micro-channel heat pipes have an evaporation functional section, the evaporation functional section is in close contact with the carbon fiber laminate, and the evaporation functional section quickly absorbs heat conducted to the carbon fiber laminate by various modules; heat dissipation pipes are arranged on the inner surface of the panel, the heat dissipation pipes cover the panel, the heat dissipation pipes have a condensation functional section, the condensation functional section is in large-area contact with the panel, the condensation functional section is connected with the evaporation functional section through a heat pipe convergence connector, and the heat pipe convergence connector is arranged at the connection between the center bearing structure and the multifunctional platform.

2. The relay satellite platform communication device for sky-ground networking according to claim 1, characterized in that, A plurality of standard slots and communication function modules are further arranged on the first side carbon fiber laminate, the standard size of the communication function module is 300×200×150 mm, and the communication function module includes an inter-satellite link module responsible for high-speed inter-satellite data transmission and a satellite-ground transceiver module responsible for satellite-ground communication; The second side carbon fiber laminate is provided with a plurality of standard slots for installing computing function modules, the standard size of the computing function module is 250×200×100 mm, and the computing function module includes a network switching module responsible for data routing and a dynamic resource scheduling module based on FPGA responsible for dynamic resource allocation; The top carbon fiber laminate is provided with a plurality of standard slots for installing management function modules, the standard size of the management function module is 300×200×200 mm, the management function module integrates power control, a lithium ion battery pack, a satellite computer, and a thermal control unit of the platform, and constitutes a platform energy, information, and control center.

3. The relay satellite platform communication device for sky-ground networking according to claim 1, characterized in that, The platform-level core unit, which does not need to be replaced in orbit or have special requirements for installation location, includes propellant tank and its pipeline system, high-precision inertial reference unit, basic core firmware and platform safety control computer.

4. The relay satellite platform communication device for sky-ground networking according to claim 1, characterized in that, The top carbon fiber laminate of the central load-bearing structure is provided with a management function module, the first side carbon fiber laminate is provided with a computing function module, and the second side carbon fiber laminate is provided with a communication function module.

5. The relay satellite platform communication device for sky-ground networking according to claim 1, characterized in that, The backboard adopts FR-4 substrate, and the total thickness is 2.4 mm. The internal layer architecture of the backboard is 12 layers, which are a ground layer, a control layer, two signal layers, four power supply layers, two signal layers, a control layer, and a ground layer from top to bottom.

6. The relay satellite platform communication device for sky-ground networking according to claim 1, characterized in that, The optical window is protected by high-strength sapphire glass, the working wavelength is 1550 nm, the communication rate can reach 10 Gbps, and the Ku-band parabolic antenna is located in the center of the first side guard plate and is an integral structure with the first side guard plate, and the working frequency covers 12-18 GHz.

7. The relay satellite platform communication device for sky-ground networking according to claim 1, characterized in that, A gradient CTE transition layer is arranged between the backboard and the carbon fiber laminate.

8. The relay satellite platform communication device for sky-ground networking according to claim 2, characterized in that, The inter-satellite link module integrates a laser communication terminal and a Ka-band phased array radio frequency front end, and the satellite-ground transponder module integrates a Ku / Ka-band transceiver and processing unit.

9. The relay satellite platform communication device for sky-ground networking according to claim 2, characterized in that, The module is inserted into the standard slot, guide rails are arranged on both sides of the inside of the standard slot, sliding blocks are arranged on both sides of the module insertion end and matched with the guide rails, the two sides of the module insertion end gradually shrink inward to form an inclined surface with a guiding function; after the module is completely connected with the standard slot, the floating blind connector at the bottom of the module provides a floating compensation of ±0.5 mm to ensure that the 240 pins can be uniformly contacted at the same time, and then the mechanical locking device at the top of the module is activated to apply a constant locking force of 20 N.

10. The relay satellite platform communication device for sky-ground networking according to claim 5, characterized in that, The four-layer power supply layer adopts 2oz copper foil for distributing 28V primary power supply and 100V high-voltage bus, with a maximum transmission power of 3000W, and integrates overcurrent and overvoltage protection functions; The four-layer signal layer is dedicated to transmitting SpaceWire high-speed differential signals, with a characteristic impedance controlled at 100Ω±10% and a transmission rate not less than 200Mbps. The signal layer adopts a stripline design and is electromagnetically shielded by the ground layer; The two-layer control layer is provided with a CAN bus network with a transmission rate of 1Mbps for platform health management and command telemetry transmission; The two-layer ground layer provides a complete reference ground plane and power return path.

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