1. Introduction In traditional shipborne radar computer systems, a dual-machine (A, B) architecture is generally adopted: Machine A is responsible for data acquisition, tracking, and processing, and is called the mission computer; Machine B is responsible for displaying and controlling the radar's overall situation and related data, and also performs operations on various interfaces, and is called the human-machine interface computer. Machines A and B exchange data through a shared storage area. In this system, both machines are ruggedized military-grade. Machine A is connected to the radar interface board, antenna azimuth interface board, etc., while Machine B needs to control and operate various interface boards, such as display interface boards, external interface boards, data storage boards, and network interface boards. Simultaneously, the system also contains various small systems for controlling radar sub-systems, such as servo systems; and GPS systems that provide ship latitude and longitude information. These small systems communicate with Machine B via serial ports. It is evident that traditional computer systems consist of many boards, each with a single function, resulting in a complex system structure, poor reliability, and low data exchange efficiency. In situations involving multiple targets, data exchange and tracking calculations may not be completed. To meet the requirements of modern radar systems—small size, powerful functionality, and ease of maintenance—this paper presents a bold improvement to the traditional radar computer system using SmartModule modules, large-scale FPGAs, and application-specific integrated circuits. The new system features fewer component boards, powerful single-board functions, a simple system structure, high reliability, high data exchange efficiency, strong scalability, and low cost. 2. Computer System Composition and Implementation The new computer system consists of two single-board computers. The task computer and the human-machine interface computer have identical hardware configurations, but they perform their respective functions through different internal software. The task computer primarily acquires data through the FPGA radar interface and performs target detection, acquisition, tracking, and computation. The use of a high-speed CPU and a large-scale FPGA significantly improves data processing capabilities and speed. The human-machine interface computer is responsible for raster display control, radar operation, data storage, and various external interface operations. The task computer and the human-machine interface computer exchange data via dual-port RAM, network, or high-speed bus. [IMG=Design of Radar Embedded Computer Based on SmartModule]/uploadpic/THESIS/2007/7/2007071810510969834Y.jpg[/IMG] As shown in Figure 1, the computer board consists of a SmartModule computer module, display interface, external interface, radar control, electronic disk, network, dual-port RAM, FPGA, etc. Clearly, compared to the old system, the new system has significantly fewer component boards and enhanced integration. The functions of many interface boards are now integrated onto a single computer board, improving system reliability and maintainability. Due to the adoption of a network, the system's external communication efficiency is greatly improved. 2.1 Introduction to SmartModule The SmartModule is a miniaturized single-chip PC system unit from Digital-Logic, a Swiss company, similar to the currently popular System-on-Chip (SOC), and compatible with standard PC/AT. It features modularity, serialization, compact structure, powerful functionality, ease of hardening, and heat dissipation. [IMG=Design of Radar Embedded Computer Based on SmartModule]/uploadpic/THESIS/2007/7/2007071810522333409P.jpg[/IMG] The actual design uses the SmartModule P5PC-266 module, and its block diagram is shown in Figure 2. Specific technical specifications are as follows: Processor: P5 266MHz; Power Supply: 5V; Cache: 256K; Memory: 64M; Two serial ports: COM1, COM2; One parallel port: LPT1; One floppy drive interface; Two EIDE interfaces; Two USB interfaces; PS/2 mouse interface; IrDA interface; Watchdog function; Timer function; Keyboard controller; Display interface: 69000 with 2M video memory; Sound card; Supports two buses: ISA and PCI; Dimensions: 85X66X14mm. 2.2 Introduction to the Design of the SmartModule-Based Computer Board Although the SmartModule is compatible with the PC/AT system, its own functions are not complete and need to be expanded accordingly to meet the embedded application of radar computer. The SmartModule-based computer board mainly includes the following parts: SmartModule P5PC-266 module, radar control interface, display interface, electronic disk, dual-port RAM, external interface, network interface, interrupt extension, etc. The main parts are briefly introduced below: (1) The large storage space of the electronic disk is necessary for system software installation, program debugging and data storage. Therefore, the system uses the DOC2000 series electronic disk of M-system for expansion, with a storage capacity of 2M~1GB. The DOC series electronic disk is small in size, simple in interface and large in capacity, and has become the preferred storage type for embedded applications. The appearance of DOC2000 is shown in Figure 3. [IMG=Design of Radar Embedded Computer Based on SmartModule]/uploadpic/THESIS/2007/7/2007071810534420287F.jpg[/IMG] (2) External Interfaces: In order to communicate and control data with other devices, such as GPS devices, missile command instruments, platform compasses, loggers, touch screens, mice, etc., it is necessary to reserve multiple serial ports and wellheads for users when networks are not widely used. Therefore, the system uses TI's TL16C554 chip to expand 8 RS232/422 serial ports on the board. (3) Network Interface: The use of Intel's 82559 dual-redundant 10/100M adaptive network card is a highlight of this system. (4) Interrupt Expansion: Since the SmartModule module itself has 16 interrupt levels and it uses most of them internally, the number of interrupts available to users is relatively small. Therefore, the interrupts need to be expanded. The system uses FPGA to expand the interrupts. (5) The FPGA completes functions such as radar interface, data detection and acquisition, decoding, and interrupt extension. The use of large-scale programmable logic devices greatly saves space and improves efficiency. 3 Conclusion This paper briefly introduces SmartModule and, combined with actual work experience, simply explains its design and application in an embedded radar computer system. The new system features fewer component boards, powerful single-board functions, simple system structure, high reliability, high data exchange efficiency, and strong scalability. It has been practically verified in a miniaturized radar and is a beneficial attempt at radar computer systems.