• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2003.10a
• /
• pp.192-195
• /
• 2003

본 논문에서는 FFT(Fast Fourier Transform)를 수행하며 이를 원격지에 전송할 수 있는 원격 모니터링 시스템을 위한 FFT서버 시스템 구축에 대하여 기술하고자 한다. 실시간으로 얻어지는 데이터를 동시에 FFT분석을 하여 이를 원격지에 전송할 수 있다. 그리고 방대한 양의 데이터의 처리와 전송과정에서 발생하는 시간적, 자원적 손실을 줄일 수 있도록 데이터를 선별하여 분석한다. 제안된 시스템은 실시간 계측 데이터에서 의미있는 데이터를 추출하고, FFT를 통해 1차 처리 후 네트워크를 통해 이를 목적지에 전달한다. 이로 인해 네트워크 자원의 보다 효율적인 사용과 감시 대상의 다양한 각도에서의 분석에 도움이 될 것으로 기대한다.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.50 no.9
• /
• pp.144-155
• /
• 2013

This paper presents a low-cost remote power-quality-failure monitoring system (RPMS) using Android App and TI MCU (micro-controller unit), which is appliable to a micro-grid. The designed RPMS testbed consists of smart nodes, a server, and Android APPs. Especially, the C2000-series MCU-based RPMS smart node that is low-cost compared to existing monitoring systems has both a signal processing function for power signal processing and a data transmission function for power-quality monitoring data transmission. The signal processing function implements both a wavelet-based power failure detection algorithm including sag, swell, and interruption, and a FFT-based power failure detection algorithm including harmonics such that reliable and real-time power quality monitoring is guaranteed. The data transmission function implements a low-complexity RPMS transmission protocol and defines a simple data format (msg_Diag) for power monitoring message transmission. We may watch the monitoring data in real time both at a server and Android phone Apps connected to the WiFi network (or WAN). We use RS-232 (or Bluetooth) as the wired (or wireless) communication media between a server and nodes. We program the RPMS power-quality-failure monitoring algorithm using C language in the CCS (Code Composer Studio) 3.3 environment.

• Journal of the Institute of Convergence Signal Processing
• /
• v.16 no.4
• /
• pp.139-148
• /
• 2015

In this paper, the optimum coding method is proposed by using open library in order to improve the performance of a software correlator developed for Korea-Japan Joint VLBI Correlator(KJJVC). The correlation system for VLBI observing system is generally implemented with hardware using ASIC or FPGA because the computational quantity is increased geometrically according to the participated observatory number. However, the software correlation system is recently constructed at a massive server such as a cluster using software according to the development of computing power. Since VLBI correlator implemented with hardware is able to conduct data processing with real-time or quasi real-time compared with mostly observational time, software correlation has to perform optimal data processing in coding work so as to have the same performance as that of the hardware. Therefore, in this paper, the experimental comparison was conducted by open-source based fftw library released in FFT processing stage, which is the most important part of the correlator system for performing optimum coding work in software development phase, such as general method using fftw library or methods using SSE(Streaming SIMD Extensions), shared memory, or OpenMP, and method using merged techniques listed above. Through the experimental results, the proposed optimum coding method for improving the performance of developed software correlator using fftw library, shared memory and OpenMP is effectively confirmed by reducing correlation time compared with conventional method.