Introduction Currently, most designs for signal transmission among components in a system employ simple point-to-point wire transmission. While this method is simple and feasible when the number of signals is small, it becomes cumbersome when dealing with a large number of signals and limited space. For example, the increased number of connectors and wires due to the large number of signals not only puts significant pressure on the structural design of a missile fuze control system but also reduces the reliability of signal transmission due to the numerous connectors. Furthermore, the large number of wires reduces the system's environmental adaptability and electromagnetic compatibility. With the development of missile fuze control system design technology, its functional requirements have become more complex, and the demands for miniaturization, reliability, and safety performance indicators are constantly increasing. Traditional point-to-point wire transmission methods are increasingly unable to meet the development requirements of such systems. As the drawbacks of traditional signal transmission designs become more apparent and digital control and network communication technologies mature, a new fieldbus transmission scheme is gaining increasing attention from designers. The design of a new signal transmission method centered on fieldbus can effectively overcome the shortcomings of traditional point-to-point wire transmission and improve the performance indicators of system signal transmission. 1 Overall Design Principles of the Scheme The implementation of signal transmission between various related components in the system is an essential part of the realization of the entire system function. Therefore, in the research and design process, it is necessary to ensure the real-time and reliable transmission of all signals during the operation of the system [1]. The specific design principles can be summarized as follows: a) Inheritance principle: Reasonably learn from and inherit the mature and reasonable design experience in traditional design schemes and apply it to the research of new system signal transmission schemes, so as to highlight the design focus, shorten the design cycle, improve efficiency, and save costs. b) Advanced principle: The fieldbus scheme itself is a major breakthrough relative to the traditional design. Therefore, in the research and design of system signal transmission, we should focus on future needs, adopt advanced methods and products as much as possible on the basis of mature technologies, and optimize the consideration of high-speed hardware and flexible and efficient communication protocols. c) Reliability principle: The new fieldbus scheme, on the one hand, brings simplification of cables, which is conducive to improving reliability. On the other hand, because of the addition of bus interfaces and self-testing tasks, the local complexity of the system has increased. The working environment on the missile is relatively harsh, which may form new fault hazards. Therefore, the selection of fieldbus must pay attention to the balance between performance and reliability, and achieve reasonable design. d) Flexibility Principle: Control systems have numerous components with varying functions and signal characteristics. During the research and design process, configurations should be flexible based on individual characteristics and overall functional requirements, employing a combination of bus and dedicated lines for a reasonable design. e) Redundancy Principle: Redundancy is a crucial element of traditional signal transmission design and a fundamental principle of bus schemes. Appropriate use of redundancy not only improves the reliability of the bus system but also enhances system performance. 2. Preliminary Design and Implementation of the Scheme According to IEC standards and the definition of the Fieldbus Foundation (FF), a fieldbus is a fully digital, serial, bidirectional communication system that connects field devices such as sensors, actuators, and controllers. Therefore, it can be used to achieve "intelligent" integration of various components in complex systems, truly forming a distributed field communication network. The following section conducts a preliminary research and analysis of the signal transmission scheme based on the design principles of a missile fuze control system, considering the signal characteristics and functional requirements of various related components. 2.1 Fieldbus Selection: Analysis and comparison of the characteristics of different types of fieldbuses such as FF, LonWorks, Profibus, CAN, and HART revealed that the CAN bus is currently the most promising fieldbus for application. CAN supports multi-master operation, allowing any node on the network to actively send information to other nodes at any time. It supports point-to-point, one-to-many, and global broadcast modes for receiving and sending data. Its advantages are mainly: multi-master bus structure; simple wiring; maximum communication rate of up to 1 Mbit/s; CAN protocol for encoding digital communication modules; and the low bit error rate of the CAN bus ensuring the reliability of data communication. Analysis of the control and testing requirements of a missile fuze control system revealed that the CAN bus can fully meet the system's control reliability and real-time requirements. However, it has shortcomings in bus data throughput. Therefore, it is considered to design separate control and test channels for the system, or to use a configurable fieldbus, such as Profibus, to accommodate different control and testing needs. 2.2 Fieldbus-based Interface Design Using a fieldbus interface to realize signal transmission between the front and back systems of a missile fuze control system and the ground measurement and control system requires research and design in both hardware and software aspects. 2.2.1 Hardware Design First, it is necessary to determine the quantity, type, and signal characteristics of the detection and control signals of each relevant component and part in the connected system. Because the number of electrical signals transmitted between the various subsystems in this system is large, they can be categorized into power lines, system control signal lines, and system test signal lines. To meet the overall system requirements and optimize signal transmission, theoretically, these signals can be transmitted via the bus after appropriate transformation. However, in practical design, the importance of each component and part should be considered based on its function and signal type. This scheme considers a design that combines a small number of dedicated lines in the main digital bus network for signal transmission, such as power signals, self-destruct signals, and battery activation signals. The specific connection relationships are shown in Figure 1. Secondly, appropriate controllers and bus adapters should be selected based on the relevant components and parts in the connected system, as shown in the "communication module" in Figure 1. This part is crucial for the system's signal transmission scheme, and this scheme has made a preliminary design for this part considering the overall system's anti-interference and security indicators. The specific principle block diagram is shown in Figure 2. 2.2.2 Software Design The software design includes three parts: CAN node initialization program, message sending program, and message receiving program. During software development, CAN bus error handling, bus isolation processing, receive filtering processing, baud rate parameter setting and automatic detection, as well as the calculation of CAN bus communication distance and number of nodes were fully considered. Some functions were appropriately reduced based on the overall system reliability requirements. 3. Significance of the Scheme Design In the signal transmission scheme of a missile fuze control system, replacing the traditional point-to-point wire method with a fieldbus is of great significance for improving the performance of the entire system's signal transmission. a) It reduces the number of wires and connectors in the system cables, alleviating the pressure on structural design and facilitating the design and implementation of a miniaturized system structure. b) It reduces the number of wires and connectors in the system cables, lowers the complexity of system cable connections, improves signal anti-interference, and enhances the electromagnetic compatibility and reliability of the miniaturized system. c) It enables system testing of the missile fuze control system in its fully assembled state and allows for time-sharing partial power-on of various components and parts within the system to complete usability checks. 4. Conclusion Although current bus transmission rates are constantly improving, they still have latency compared to point-to-point dedicated line transmission. This requires designers to fully consider the bus's transmission capabilities and its ability to meet the real-time and reliability requirements of the control system when designing control system solutions. Therefore, many technical details in this research process still need to be studied and verified theoretically and practically. Since the interface circuit occupies a certain amount of space in the system, and considering the miniaturization requirements of a missile fuze control system, chip integration technology can also be considered in this research process.