High-reliability wireless communication device for satellite-rocket two-way information interaction
By using a star-shaped wireless network topology and hardware redundancy design, the problem of high-reliability wireless communication between satellites and rockets in the "one rocket, multiple satellites" launch scenario was solved, achieving low-latency, high-throughput information exchange and reliable separation processes.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-09
- Publication Date
- 2026-03-13
AI Technical Summary
Traditional wired communication methods cannot meet the reliability of information exchange between satellites and rockets and the ability to handle multiple concurrent nodes in the scenario of "one rocket, multiple satellites" launch, and there is a risk of misreceiving and triggering commands during the separation process.
It adopts a star wireless network topology architecture, uses a high-performance Bluetooth MCU and a 2.4G proprietary protocol stack, and combines hardware redundancy design and software timing control to ensure the concurrency capability of multiple nodes and the robustness of the separation process.
It achieves low-latency, high-throughput wireless communication, prevents misreceived and mistriggered commands, ensures the robustness of wireless communication during the separation process, and has a bit error rate of less than 10⁻⁷.
Smart Images
Figure CN121664271A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of rocket-satellite wireless communication, specifically relating to a highly reliable wireless communication device for two-way information exchange between a satellite and a rocket. Background Technology
[0002] Traditional launch vehicles typically employ a "one rocket, one satellite" configuration, where wired communication via a fixed interface suffices for bidirectional data transmission between the rocket and the satellite. However, with the recent proposal and accelerated construction of large-scale low-Earth orbit satellite internet constellations, the number of satellites launched per rocket has jumped from one to dozens, making "one rocket, multiple satellites" launches the mainstream. Therefore, traditional wired communication methods, limited by complex physical interfaces and cable arrangements, poor dynamic networking compatibility, and the high risk of entanglement and collision during separation, are no longer adequate to meet the information exchange requirements between the rocket and the satellite in "one rocket, multiple satellites" scenarios.
[0003] Against this backdrop, wireless communication has become an inevitable choice to mitigate the aforementioned risks. However, at the same time, large-scale constellations place higher demands on the reliability of wireless communication: wireless communication devices must support the establishment of low-latency, high-throughput connections between the rocket and multiple satellites simultaneously, i.e., they must have multi-node concurrency capabilities; before the separation of the satellite and the rocket, it is necessary to prevent the misreceipt and mis-triggering of commands, which could lead to separation before the satellite's fairing is jettisoned; at the moment of separation, it is necessary to ensure that commands can be reliably transmitted without packet loss under large impacts and satellite attitude adjustments, i.e., the robustness of wireless communication during the separation process.
[0004] Currently, in applications with a limited number of satellites, communication between rockets and satellites typically uses traditional wired connections, such as umbilical cables. However, in densely deployed satellite constellation systems, satellites usually separate after reaching orbit using a random unlocking and passive diffusion method, without achieving orderly and controllable separation. Therefore, highly reliable wireless communication between rockets and satellites has not been considered.
[0005] Traditional launch vehicles mostly employ wired separation control. However, with "multiple satellite launches" becoming the mainstream, wired communication and separation control can no longer meet the information exchange requirements between the satellites and the launch vehicle. This invention aims to solve the problem of achieving highly reliable command transmission and wireless communication between multiple satellites and the launch vehicle when multiple satellites communicate or separate as required in a "multiple satellite launch" scenario.
[0006] To achieve this objective, the design of the wireless communication device needs to be considered. The problems to be solved include:
[0007] (1) It needs to support the rocket and multiple satellites to establish low-latency, high-throughput, and highly reliable wireless connections at the same time, i.e., multi-node concurrency capability;
[0008] (2) Before the star and rocket separate, it is necessary to prevent the command from being received or triggered incorrectly, which would cause the separation to occur before the shield is jettisoned;
[0009] (3) At the moment of separation of the star and the rocket, it is necessary to ensure that the command can be transmitted reliably without packet loss, that is, the robustness of wireless communication during the separation process. Summary of the Invention
[0010] Overcoming the shortcomings of existing technologies, this invention proposes a highly reliable wireless communication device for two-way information exchange between satellite and rocket. It adopts a star-shaped wireless network topology, with the central device using a high-performance Bluetooth MCU and a 2.4G proprietary protocol stack to control the transmission and reception of the satellite-mounted nodes, supporting expansion and multi-node concurrency capabilities. In terms of hardware, the separation signal output circuit uses two pairs of relay contacts connected in parallel to avoid malfunctions caused by a single contact being accidentally connected. Simultaneously, all commands undergo a five-factor authentication process to prevent false triggering. The entire device is constrained in software timing to prevent false triggering or reception of commands. The central device and end-node hardware platform architecture are fully redundant, and anti-interference designs are employed for critical interface circuits, effectively ensuring the robustness of wireless communication under the impact of satellite-rocket separation.
[0011] A highly reliable wireless communication device for two-way information exchange between a rocket and a satellite includes onboard equipment and onboard equipment. The onboard equipment and the onboard equipment are not connected by cables, and information transmission is completed through a wireless channel.
[0012] The onboard equipment includes a central device and an antenna, both mounted on the satellite support at the rocket end. The central device is powered by the onboard measurement system, receives rocket separation commands sent by the control system, and communicates with the telemetry system. The central device is mainly used for converting and sending onboard separation commands or satellite power-on commands.
[0013] The on-board equipment is a node device. The hardware of each node device is completely identical, with only the unit number being different. The node device is installed on the stacking column of the corresponding satellite. After receiving the wireless signal and judging it correctly, it sends a level signal to the separation device to drive the separation device to separate, or sends power-on and unified timing commands to the satellite. The node device is mainly used for the execution and status monitoring of on-board separation operations.
[0014] All onboard equipment employs a fully redundant hardware architecture to enhance the reliability of the hardware platform.
[0015] The central equipment includes a power module, an interface module, a wireless communication module, and a software design module. The central equipment receives the launch signal and separation / power-on command from the rocket system, and converts the separation / power-on command into a separation command for the satellite-rocket separation device. The command is then transmitted via the wireless communication module according to a predetermined timing sequence. At the same time, the satellite can be synchronized with the time at launch to ensure that the satellite operates at a unified time zero point, which facilitates the satellite's own separation timing.
[0016] Furthermore, the power module has two power conversion methods: 28V to 5V and 5V to 1.8V. The 5V voltage is used to power the interface module, and the 1.8V voltage is used to power the wireless communication module.
[0017] Furthermore, the interface module includes an RS-422 communication interface, a converter interface, and a conversion acquisition interface. The RS-422 communication interface uploads the status parameters and separation status of the central and node devices to the rocket system. The converter interface provides four +15V converter interfaces for powering external loads such as sensors. The conversion acquisition interface is used to acquire power-on, separation, and takeoff signals from the rocket system. It reduces the 28V acquired signal to below 5V through an isolation operational amplifier and sends the output voltage to the MCU for voltage isolation conversion. It adopts a five-decision-three (five retransmissions of the command, three decisions) error correction measure and uses a GH-6631 optocoupler for isolation to prevent overcurrent and overvoltage that may occur when the device itself fails from damaging other devices directly or indirectly connected to it through the interface. At the same time, it can effectively prevent false triggering caused by interference and improve the reliability of the interface.
[0018] Furthermore, the wireless communication module is responsible for signal processing, timing implementation, and bidirectional information transmission and reception with the node device via wireless communication.
[0019] Furthermore, the software design module includes a node device wake-up module and an instruction issuance module, both of which adopt a proprietary wireless transceiver protocol stack;
[0020] The node device wake-up module is initiated by the central device when the node device is in a sleep state, and sends a device wake-up command to the node device to put the node device into working state; the command sending module is used to send power-on, take-off and separation commands to the slave nodes after the silent window ends; the proprietary wireless transceiver protocol stack has a channel bandwidth of 1MHz and a frequency band of 2.4GHz ISM.
[0021] The software design employs multiple reliability measures. All commands are broadcast with a response, i.e., a message confirmation and reply mechanism. After each broadcast or command is sent, the node device is required to reply with its own response. If the received response times out, it enters the corresponding processing branch, ensuring the reliability of command reception. The software workflow adopts strict timing control. For example, after receiving the launch signal from the rocket, the satellite will perform unified timing and start timing according to the predetermined command masking time (the time can be adjusted according to different mission adaptability). Only after the timing time expires will it continue to wait for system commands and prepare to receive the satellite separation signal, which can effectively prevent the misreception of commands and the accidental triggering of separation actions.
[0022] The node device includes a power module, an interface module, and a software design module; the node device receives wireless power-on / takeoff / separation commands sent by the central device, judges them, outputs corresponding signals, and reserves a satellite telemetry interface.
[0023] Furthermore, the interface module includes a converter module interface and a switch control module interface. The converter module interface provides four +5V converter interfaces for powering the acquisition of external non-energized commands such as limit switches. Physical isolation is used between circuits to ensure reliability, with a maximum power supply current of 20mA. The switch control module interface sends a separation signal to the electric drive nut. After receiving the switch closing command from the core processing unit, the satellite separation control module uses the separation battery as a power source to provide the satellite with a 28V 200ms voltage pulse signal (peak current 3A) to drive the satellite to separate. The switch control module circuit adopts a 2-main, 2-backup mode. Simultaneously, a single-channel separation control circuit uses four solid-state relays connected in series and parallel. A reverse peak suppression circuit is designed on the output path to eliminate reverse voltage caused by inductive loads when the relays are disconnected.
[0024] Furthermore, the software design module includes a sleep module and a system status monitoring module; the sleep module adopts a sleep strategy of sleeping for 1 second and listening for 10 ms to control the power consumption of node devices.
[0025] The beneficial effects of this invention are as follows:
[0026] (1) It can achieve a wireless communication bit error rate of not less than 10⁻⁷.
[0027] (2) A star network topology is adopted. The central device uses a high-performance Bluetooth MCU and a 2.4G proprietary protocol stack to control the transmission and reception of the upper-end nodes and supports expansion, thus solving the problem of multi-node concurrency.
[0028] (3) The hardware platform architecture of the wireless communication device is fully redundant. Anti-interference design is adopted for the key command receiving circuits such as take-off, power-on and separation signals, which can effectively ensure the robustness of wireless communication in actual flight scenarios.
[0029] (4) The wireless communication device separates the signal transmission circuit and adopts the working mode of two pairs of solid-state relay contacts in series to avoid malfunction caused by a pair of contacts being accidentally connected. At the same time, it performs a five-factor judgment on all commands to prevent false triggering.
[0030] (5) The wireless communication device is designed with functions such as shielding trigger timing and message reply confirmation in the software timing to constrain the timing process and prevent the command from being triggered or received incorrectly. Attached Figure Description
[0031] Figure 1This is a schematic diagram of a highly reliable wireless communication device for two-way information exchange between satellites and rockets.
[0032] Figure 2 This is a flowchart of the workflow of the present invention;
[0033] Figure 3 This is a diagram illustrating the sending of a heartbeat packet;
[0034] Figure 4 This is a block diagram of the hardware principle of the central equipment;
[0035] Figure 5 This is a block diagram of the power module.
[0036] Figure 6 This is a schematic diagram of a 28V to 5V power supply.
[0037] Figure 7 This is a schematic diagram of a 5V to 1.8V power supply.
[0038] Figure 8 This is a block diagram of the RS-422 communication interface module.
[0039] Figure 9 , Figure 10 This is a schematic diagram of an RS422 communication interface;
[0040] Figure 11 This is the circuit diagram of the converter module;
[0041] Figure 12 This is the circuit diagram for the takeoff, power-on, and separation signal interfaces;
[0042] Figure 13 This is a block diagram of the wireless communication module.
[0043] Figure 14 This is the timing diagram for the central device to wake up the node devices;
[0044] Figure 15 This is a satellite power-on timing diagram;
[0045] Figure 16 It is a channel distribution diagram of a proprietary wireless communication protocol stack;
[0046] Figure 17 This is a schematic diagram of wireless communication channel pre-allocation;
[0047] Figure 18 This is a hardware block diagram of the node device;
[0048] Figure 19 This is a block diagram of the power module.
[0049] Figure 20 It is a block diagram of a discrete circuit;
[0050] Figure 21It is a series circuit;
[0051] Figure 22 This is a diagram illustrating the sleep and wake-up processes of node devices;
[0052] Figure 23 This is a diagram of the node device system status monitoring module. Detailed Implementation
[0053] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection claimed by the present invention.
[0054] A highly reliable wireless communication device for two-way information exchange between satellites and rockets, such as Figure 1 As shown, it consists of two parts: onboard equipment and satellite equipment. The onboard equipment and satellite equipment are not connected by cables, and information transmission is completed through wireless channels.
[0055] The onboard equipment includes central equipment and antennas, both mounted on the satellite support at the rocket's end. The central equipment is powered by the onboard measurement system, receives rocket separation commands from the control system, and communicates with the telemetry system. The central equipment is primarily used for converting and transmitting onboard separation commands or satellite power-on commands.
[0056] The on-board equipment consists of node devices, each with identical hardware, differing only in its serial number. Node devices are installed on stacking pillars corresponding to their respective satellites. Power is supplied internally. Upon receiving and correctly identifying a wireless signal, each node sends a voltage level signal to the separation unit to drive separation, or sends power-on and unified timing commands to the satellite. The node devices are primarily used for executing on-board separation operations and monitoring their status.
[0057] like Figure 2As shown, according to system requirements, the wireless system's operating sequence can be broken down into the following steps: 1. After the entire system is powered on, the master node sends a wake-up command to all slave nodes. Each slave node exits its sleep state, enters full-power operation, and reports its status information. The master node summarizes the telemetry parameters of the slave nodes and reports them to the rocket system, awaiting the next command from the rocket system; 2. The rocket system sends a satellite power-on signal, and the master node broadcasts the satellite power-on command. After receiving the command, each slave node sends a power-on level signal to the satellite, and the satellite is powered on; 3. The rocket system sends a takeoff signal, and the master node broadcasts a unified satellite timing command. After receiving the command, each slave node sends a timing level signal to the satellite, and the satellite achieves unified timing, enabling it to complete its own separation timing; 4. The rocket system sends a satellite separation signal, and the master node sends the satellite separation command in sequence. After receiving the command, each slave node sends a separation level signal to the satellite in sequence, and the satellite completes orderly separation. After separation, the satellite continuously reports its own status information, which is then reported by each slave node to the master node. The master node summarizes the telemetry parameters of the slave nodes, monitors the execution of commands in real time, and finally reports to the rocket system.
[0058] To improve system reliability, the software employs multiple reliability design measures in its timing design. All commands are broadcast with a response, i.e., a message confirmation and reply mechanism. After each broadcast or command is sent, the node device is required to reply with its own response. In the event of a timeout upon receiving a response, the system enters the appropriate processing branch to ensure the reliability of command reception. In addition, the workflow employs strict timing control. For example, after receiving the launch signal from the rocket, the satellite performs unified timing and each satellite begins timing according to a pre-defined command masking time (the time can be adjusted according to different mission adaptability). Only after the timing time expires will the satellite continue to wait for system commands and prepare to receive the satellite separation signal, effectively preventing misreceived commands and accidental triggering of separation actions.
[0059] The instruction sets of each component in the wireless communication protocol stack are described below:
[0060] 1. Heartbeat command
[0061] The heartbeat command set is used to maintain the connection between devices. By periodically sending heartbeat signals, the central device can detect the online status and health status of each node device. If no heartbeat feedback signal is received from a node device for an extended period, the central device can determine that the node may be offline or malfunctioning, and take recovery measures such as re-wake-up. Figure 3 This is a diagram illustrating the sending of a heartbeat packet.
[0062] After the node device is woken up, the central device periodically sends heartbeat packets to it to maintain the connection.
[0063] Table 1 Heartbeat Packet Data Structure
[0064] Frame header flags Frame length Frame number Frame instructions CRC check EB90 0x0B 2 bytes AAAA 4 bytes
[0065] 2. Wake-up command
[0066] The wake-up command set is used to activate devices in a dormant state. The central device can send a wake-up command to wake up specific node devices and put them into working state so that they can receive and process subsequent commands or data.
[0067] Table 2 Wake-up Packet Data Structure
[0068] Frame header flags Frame length Frame number Frame instructions CRC check EB90 0x0B 2 bytes BBBB 4 bytes
[0069] 3. Message confirmation reply
[0070] Message acknowledgment replies are used to ensure that messages are correctly received after being sent. After successfully receiving and processing a message, a node device returns an acknowledgment message (ACK) with the corresponding message ID. The sending device verifies the success of message transmission through acknowledgment messages, thereby improving communication reliability and reducing the risk of data loss.
[0071] Table 3 Message Confirmation Packet Data Structure
[0072]
[0073] By default, message confirmation commands are sent from the central device to the node device in response to the command, or from the central device after the node device reports its device status parameters. If no response is received within a specific time or confirmation fails (e.g., CRC check failure), the sending device will resend the command.
[0074] 4. Status Parameter Commands
[0075] The status parameter instruction set is used for status synchronization and information sharing between the central device and node devices. Through this instruction set, the central device can obtain the real-time operating status and performance parameters of the node devices to confirm whether the separation was successful. Status parameters include the node device's battery voltage and separation status, among other parameters.
[0076] Table 4. State Parameter Package Data Structure
[0077]
[0078] 5. Satellite separation command
[0079] The satellite separation command set is primarily used to control and execute satellite separation operations. This command set ensures that commands are delivered at the correct time and that their execution is confirmed by other command sets (message confirmation command sets), thereby ensuring precise mission implementation. Commands are sent continuously starting at the designated time.
[0080] Table 5 Satellite Separation Package Data Structure
[0081] Frame header flags Frame length Frame number Frame instructions CRC check 0xEB90 0x32 2 bytes 41-byte variable 4 bytes
[0082] A. Central Equipment
[0083] The block diagram of the rocket end center equipment system is as follows: Figure 4 As shown, the entire hardware system features a primary and backup redundant design to improve product reliability. The central device connects to four omnidirectional antennas via four radio frequency interfaces.
[0084] The rocket-end central equipment primarily receives launch signals and separation / power-on commands from the rocket system, converts these commands into separation commands for the satellite-rocket separation device, and transmits them via a wireless communication module according to a predetermined timing sequence. Simultaneously, it can synchronize the satellite's time at launch, ensuring the satellite operates at a unified zero point, facilitating its own separation timing. The working principles of each functional module of the central equipment are as follows:
[0085] 1) Power module
[0086] like Figure 5 As shown, the power module has two power conversion methods: 28V to 5V and 5V to 1.8V. The 5V voltage is used to power the RS-422 interface module, and the 1.8V is used to power the wireless communication module. The secondary power supply power requirements are shown in Table 6.
[0087] Table 6 Power Conversion Requirements
[0088]
[0089] The 28V to 5V converter uses the TEN3-2411N module, and the schematic diagram is shown below. Figure 6 As shown. Its principle is that the external 28V power supply passes through the reverse polarity protection diode D1, then through the TVS chip SMAJ30CA and the input capacitor before entering the power module U15, and then outputs a 5V voltage in isolation.
[0090] The 5V to 1.8V power supply is implemented using TI's DC-DC step-down chip TPS62A02DRLR, as shown in the schematic diagram. Figure 7 As shown.
[0091] 2) Interface module
[0092] a) RS-422 communication interface
[0093] This module primarily uploads the status parameters and separation status of the central and node equipment to the rocket system. The communication interface boasts high anti-interference capabilities and stability, ensuring reliable data transmission during launch and flight.
[0094] The PCM communication signal uses a non-isolated RS422 interface. The interface transceiver controller uses the ADM2687 manufactured by Analog Devices, which is an isolated RS422 interface chip with a maximum data rate of 500kbps, meeting the requirement of a communication rate of not less than 200kbps. A level conversion chip is used to connect the RS-422 transceiver controller and the wireless communication module to adjust interface matching. The interface circuit configuration is as follows: Figure 8 As shown in the figure, the RS422 communication interface schematic is as follows: Figure 9 , Figure 10 As shown.
[0095] b) Converter module interface
[0096] The central node provides four +15V converter interfaces for powering external loads such as sensors. The converter module receives power from the +28V bus and converts it to 15V for external power supply via DC / DC conversion, with a maximum supply current of 500mA. The converter module circuit is as follows: Figure 11 As shown.
[0097] c) Convert the acquisition interface
[0098] The conversion and acquisition interface is used to acquire power-on, separation, and launch signals from the rocket system. It reduces the 28V acquired signal to below 5V using an isolation operational amplifier, and then sends the output voltage to the MCU for voltage isolation conversion. The three signal interface circuits are identical, capable of pulse width judgment, and employ a five-decision-three-decision error correction measure (five command retransmissions, three decision-makings) to improve anti-interference capabilities. Simultaneously, the receiving end uses a GH-6631 optocoupler for isolation, preventing overcurrent and overvoltage damage to other directly or indirectly connected devices due to equipment failure. It also effectively prevents false triggering caused by interference, improving interface reliability. The interface circuit configuration is as follows: Figure 12 As shown.
[0099] 3) Wireless communication module
[0100] The wireless communication module is responsible for signal processing, timing implementation, and bidirectional information transmission and reception with node devices via wireless communication. Based on a high-reliability design philosophy, the core chip of the wireless communication module is the nRF5340 SoC, currently the most advanced low-power Bluetooth MCU on the market, integrating core functions such as comprehensive baseband processing, RF signal conversion, AD / DA sampling, and security protocol control.
[0101] Building upon this, to achieve the required communication distance of 100m, an integrated RF front-end is incorporated into the SoC RF interface to work in conjunction with the nRF5340. This RF front-end performs power amplification in the output direction, low-noise amplification in the input direction, and interface matching.
[0102] The principle block diagram of the wireless communication module is as follows: Figure 13 As shown.
[0103] 4) Software Design
[0104] The software design includes multiple modules, including: a node device wake-up module, a system status feedback module, a satellite power-on and separation command issuance module, and a proprietary wireless transceiver protocol stack.
[0105] a) Node device wake-up module
[0106] The node wake-up module is initiated by the central device when the node device is in a sleep state. It sends a device wake-up command to the node device to put the node device into a working state. Figure 14 The timeline for the central device to actively wake up the node devices is shown. Taking the completion of the self-test by the central device upon power-on as the time reference, the central device continuously sends satellite wake-up commands to the node devices through a predefined private node channel. When the node devices detect the wake-up command in sleep mode, they switch to working mode.
[0107] b) Separation / Power-on Command Issuance Module
[0108] Figure 15 The diagram shows the satellite power-on timing sequence, with the timeline representing the rocket launch and satellite separation processes from left to right. Considering that satellite separation is not permitted before fairing jettisoning, a shielded trigger function is incorporated into the timing design. The system remains silent within a preset time window. If the central device receives a separation command signal during the shielded trigger phase, it discards it directly without converting it into a wireless command for transmission, preventing false triggering and improving reliability. After the set time window, the node devices sequentially receive commands from the central device and execute the separation of the corresponding satellite.
[0109] c) Proprietary wireless communication protocol stack channel pre-allocation
[0110] Figure 16 This diagram shows the channel distribution within the 2.4GHz ISM band, allocated using a proprietary communication protocol, with a bandwidth of 80MHz. The orange channel in the middle is the broadcast channel, used by the central equipment to broadcast wake-up commands to each node. The other blue channels are private channels for each node device; only the node device and the rocket's central equipment communicate on their respective blue channels, which are not used by other nodes. These private channels are evenly distributed on both sides, numbered from 0 to 50, with a channel bandwidth of 1MHz. There are a total of 83 channels within the 2.4GHz ISM band. Assuming one channel is used per node device, a maximum of 83 satellite-end node devices can simultaneously communicate with the central equipment online.
[0111] Before the devices enter the system, the communication channels of each wireless communication device are first preset, such as... Figure 17As shown, the regulations stipulate that only the rocket-end central equipment is allowed to send wake-up commands on the broadcast channel; while the central equipment and corresponding node equipment are allowed to exchange information on the private channel.
[0112] In the proprietary protocol stack, a pre-allocation method is first used to allocate channels to each node, allowing only specific frequencies for communication. Based on this, communication is time-division multiplexed, with the central device acting as the master controller to schedule information transmission and command sending from each node. In the underlying protocol, after receiving a command, the device performs encoding and identification; only after successful identification does it begin parsing the data packet content. This avoids the possibility of channel collisions and achieves highly reliable wireless communication with one master and multiple slaves.
[0113] B. Node devices
[0114] The block diagram of the satellite end node equipment system is as follows: Figure 18 As shown, the entire hardware system features a primary and backup redundant design, with the antenna and node devices integrated into a single design.
[0115] The satellite-end node equipment primarily receives wireless separation / power-on commands from the central equipment, judges the command, outputs separation / power-on signals, and reserves a satellite telemetry interface. To reduce design costs and enhance versatility, the node equipment maintains consistency with the central equipment in some module designs. The integrated design is divided into three functional modules: a power supply module, a wireless communication module, and a satellite separation control module. The working principles of each module are as follows.
[0116] 1) Power module
[0117] The power module schematic diagram is as follows: Figure 19 As shown. The power supply input is a battery (3.7V, actual range: 2.75V~4.2V). The power supply section has two power conversion options: DC / DC 1.8V and DC / DC 5V. The 1.8V is used for powering the MCU and RF front-end, with an input voltage range of 2.75V~5.0V. The 5V voltage is used for powering the RS422 interface and the optocoupler (separate).
[0118] 2) Interface module
[0119] a) Converter module interface
[0120] The node provides four +5V converter interfaces for powering the acquisition of external, non-energized commands such as those from limit switches. The hardware design of this module is identical to that of the central equipment, but physical isolation is used between circuits to ensure reliability, with a maximum supply current of 20mA.
[0121] b) Switch control module interface
[0122] The satellite separation control circuit sends a separation signal to the electric drive nut. After receiving the switch closing command from the core processing unit, the satellite separation control module uses the separation battery as a power source to provide the satellite with a 28V 200ms voltage pulse signal (peak current 3A) through this circuit to drive the satellite to separate.
[0123] Each node device has four separation control circuits (two primary and two backup), and under normal circumstances, only two of these circuits are used to complete the separation operation. To ensure separation reliability, the two separation control circuits of the node device are connected to two electric drive nuts on the satellite. This ensures redundant and reliable separation even when two node devices are installed on a single satellite.
[0124] The single-channel separation control circuit uses four solid-state relays connected in series and parallel to avoid malfunctions caused by a pair of contacts accidentally closing or failures caused by a pair of relays malfunctioning, thus improving the inherent reliability of the circuit. Simultaneously, a reverse peak suppression circuit is designed on the output path to eliminate reverse voltage caused by inductive loads when the relays are disconnected. See the separation circuit block diagram below. Figure 20 As shown, the main and backup block diagrams are the same.
[0125] Each of the separate control circuits has two independent pins controlled by the MCU, with no shared pins. This avoids malfunctions caused by a single abnormal control pin of the MCU connecting the series path, and also avoids a fault mode where the failure of a single pin of the MCU causes the other path to also malfunction.
[0126] The solid-state relay selected in this solution is the Toshiba industrial-grade TLP3547, which meets the requirements of 28V power-on / disconnection signal and 3A current. A series circuit is shown below. Figure 21 As shown.
[0127] 3) Software Design
[0128] The software design includes multiple modules, including: a hibernation module, a system status monitoring module, a system status feedback module, a satellite separation control module, and a proprietary wireless transceiver protocol stack.
[0129] a) Hibernation module
[0130] The satellite node device of the wireless communication equipment enters a sleep state upon power-on. In sleep mode, most functions of the device's MCU chip are disabled, with only the clock and some main control functions retained for periodic channel monitoring. This device currently employs a sleep strategy of 1 second in sleep mode and 10ms in monitoring to control node power consumption. During the monitoring process in sleep mode, only channel reception is enabled to ensure the reception of wake-up commands.
[0131] After the device is fully woken up, the satellite node devices of the wireless communication equipment begin operating at full power. In summary, the rocket-side central equipment, acting as the master control unit, needs to continuously send heartbeat packets to the satellite node devices to keep them online. To reduce power consumption, the node devices start timing if they do not receive a heartbeat packet; if no heartbeat packet is received after 30 minutes, the node devices consider the central equipment offline and re-enter sleep mode. Figure 22 This is a schematic diagram of node device hibernation and wake-up.
[0132] b) System status monitoring module
[0133] Figure 23 This is a diagram of the node device system status monitoring module. First, this module begins with the initialization of the timer. Each time the timer expires, the system status is updated, including the power supply voltage of the node device, the voltage of critical nodes, the disconnection status of the node device, and the chip temperature, to promptly determine the device status.
[0134] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. A highly reliable wireless communication device for two-way information exchange between satellites and rockets, characterized in that, It includes onboard equipment and satellite-based equipment. The onboard equipment and satellite-based equipment are not connected by cables, and information transmission is accomplished through wireless channels. The onboard equipment includes a central device and an antenna, both mounted on the satellite support at the rocket end. The central device is powered by the onboard measurement system, receives rocket separation commands sent by the control system, and communicates with the telemetry system. The central device is mainly used for converting and sending onboard separation commands or satellite power-on commands. The on-board equipment is node equipment, and the hardware of each node equipment is completely identical, with only the individual unit number being different. The node device is installed on the stacking column of the corresponding satellite. After receiving the wireless signal and judging it correctly, it sends a level signal to the separation device to drive the separation device to separate, or sends power-on and unified timing commands to the satellite. The node device is mainly used for the execution and status monitoring of on-board separation operations. All onboard equipment employs a fully redundant hardware architecture.
2. The highly reliable wireless communication device for two-way information exchange between satellites and rockets according to claim 1, characterized in that, The central equipment includes a power module, an interface module, a wireless communication module, and a software design module. The central equipment receives the launch signal and separation / power-on command from the rocket system, and converts the separation / power-on command into a separation command for the satellite-rocket separation device. The command is then transmitted via the wireless communication module according to a predetermined timing sequence. At the same time, the satellite can be synchronized with the time at launch to ensure that the satellite operates at a unified time zero point, which facilitates the satellite's own separation timing.
3. A highly reliable wireless communication device for two-way information interaction between satellites and rockets according to claim 2, characterized in that, The power module has two power conversion functions: 28V to 5V and 5V to 1.8V. The 5V voltage is used to power the interface module, and the 1.8V voltage is used to power the wireless communication module.
4. A highly reliable wireless communication device for two-way information interaction between satellites and rockets according to claim 2, characterized in that, The interface module includes an RS-422 communication interface, a converter interface, and a conversion acquisition interface; the RS-422 communication interface uploads the status parameters and separation status of the central equipment and node equipment to the rocket system. The converter interface provides four +15V converter interfaces for powering external loads; the conversion acquisition interface is used to acquire power-on, separation and takeoff signals from the rocket system. The 28V acquired signal is reduced to below 5V through isolation operational amplifiers, and the output voltage is sent to the MCU to complete voltage isolation conversion. It adopts a five-decision-three error correction measure, that is, five retransmissions of the command and three decisions, and uses GH-6631 optocouplers to achieve isolation.
5. A highly reliable wireless communication device for two-way information interaction between satellites and rockets according to claim 2, characterized in that, The wireless communication module is responsible for signal processing, timing implementation, and bidirectional information transmission and reception with node devices via wireless communication.
6. A highly reliable wireless communication device for two-way information interaction between satellites and rockets according to claim 2, characterized in that, The software design modules include a node device wake-up module and a command issuance module, both of which adopt a proprietary wireless transceiver protocol stack. The node device wake-up module is initiated by the central device when the node device is in a sleep state, and sends a device wake-up command to the node device to put the node device into working state; the command sending module is used to send power-on, take-off and separation commands to the slave nodes after the silent window ends; the proprietary wireless transceiver protocol stack has a channel bandwidth of 1MHz and a frequency band of 2.4GHz ISM. All instructions are broadcast with a response, i.e., a message confirmation and reply mechanism. After each broadcast or instruction is sent, the node device is required to reply with its own response. If the response times out, the corresponding processing branch is entered.
7. A highly reliable wireless communication device for two-way information exchange between satellites and rockets according to claim 1, characterized in that, The node device includes a power module, an interface module, and a software design module; the node device receives wireless power-on / takeoff / separation commands sent by the central device, judges them, outputs corresponding signals, and reserves a satellite telemetry interface.
8. A highly reliable wireless communication device for two-way information interaction between satellites and rockets according to claim 7, characterized in that, The interface module includes a converter module interface and a switch control module interface; the converter module interface provides four +5V converter interfaces for power supply to acquire external non-powered commands. The switch control module interface is used to send a separation signal to the electric drive nut. After receiving the switch closing command from the core processing unit, the satellite separation control module uses the separation battery as a power source to provide the satellite with a 28V 200ms voltage pulse signal and a peak current of 3A to drive the satellite to achieve separation. The switch control module circuit adopts a 2-main-2-backup mode, while the single-channel separation control circuit uses 4 solid-state relays connected in series and parallel. A peak suppression circuit is designed on the output path.
9. A highly reliable wireless communication device for two-way information interaction between satellites and rockets according to claim 7, characterized in that, The software design module includes a hibernation module and a system status monitoring module; the hibernation module adopts a hibernation strategy of hibernation for 1 second and listening for 10 ms to control the power consumption of node devices.