This paper presents a new topology of distributed measurement systems, which apply fieldbus-based intelligent sensors. Based on the framework, a novel intelligent measurement system, which provides output of measured data and data uncertainty simultaneously, is invented. The distributed measurement system is developed to connect intelligent sensors, intelligent actuators, and other intelligent control units together, where their intelligent functions are given by the availability of internal computing power and digital communications. With the help of fieldbus, intelligent sensors applying novel advanced methods of measurement technology are described. As an example to illustrate the proposed distributed system and advantages offered by fieldbus-based intelligent sensors, an implementation of intelligent frequency-output sensors attributed to distributed systems is presented. The intelligent eddy-current sensor that applies computing algorithms for separating sensor data errors and predicting sensor status is introduced. The contribution of blind source separation is highlighted. In the end, the test results and conclusions are provided