The analog-based Ex-core Neutron Flux Monitoring System (ENFMS) in Korean Nuclear Power Plants (NPPs) has been performing its intended functions successfully for a long time. On the other hand, the primary concern with the extended use of analog systems is the aging effect, such as mechanical failures, environmental degradation, and obsolescence. The transition to a digital-based Man-Machine Interface Systems (MMIS) in Korea and other countries has been accelerating, but some systems are still analog-based IC systems, such as the ENFMS in APR1400 NPPs. Digitalized ENFMS can become a reality using computers and microprocessors owing to the progress in digital electronics and information technology. This paper presents the result of the first phase of the research on the digitalization of the ENFMS signal processing electronics for NPPs operated or produced in Korea. It has two main parts: (1) review engineering bases of ex-core neutron flux monitoring system, including nuclear engineering, instrumentation techniques, and analog and digital signal processing techniques, and (2) analysis of analog signal processing electronics of ENFMS for OPR1000 and APR1400 power plants. They are prerequisite to the second phase of the research which is the detailed implementation of the digitalization.

韩国核电站 (NPP) 中基于模拟的 Ex 堆芯中子通量监测系统 (ENFMS) 长期以来一直成功地执行其预期功能。另一方面，模拟系统扩展使用的主要问题是老化效应，例如机械故障、环境退化和过时。韩国和其他国家向基于数字的人机界面系统 (MMIS) 的过渡一直在加速，但一些系统仍然是基于模拟的 IC 系统，例如 APR1400 核电厂中的 ENFMS。由于数字电子和信息技术的进步，数字化 ENFMS 可以使用计算机和微处理器成为现实。本文介绍了韩国运营或生产的核电厂 ENFMS 信号处理电子设备数字化研究第一阶段的结果。主要分两部分：（1）核外中子通量监测系统工程基础回顾，包括核工程、仪器仪表技术、模拟和数字信号处理技术；（2）OPR1000 ENFMS模拟信号处理电子学分析和 APR1400 发电厂。它们是第二阶段研究的先决条件，即数字化的详细实施。(2) OPR1000 和 APR1400 发电厂 ENFMS 模拟信号处理电子器件分析。它们是第二阶段研究的先决条件，即数字化的详细实施。(2) OPR1000 和 APR1400 发电厂 ENFMS 模拟信号处理电子器件分析。它们是第二阶段研究的先决条件，即数字化的详细实施。