分类: 天文学 >> 天文仪器与技术 提交时间: 2024-04-18 合作期刊: 《天文技术与仪器(英文)》
摘要:Radioheliographs can obtain solar images at high temporal and spatial resolution, with a high dynamic range. These are among the most important instruments for studying solar radio bursts, understanding solar eruption events, and conducting space weather forecasting. This study aims to explore the effective use of radioheliographs for solar observations, specifically for imaging coronal mass ejections (CME), to track their evolution and provide space weather warnings. We have developed an imaging simulation program based on the principle of aperture synthesis imaging, covering the entire data processing flow from antenna configuration to dirty map generation. For grid processing, we propose an improved non-uniform fast Fourier transform (NUFFT) method to provide superior image quality. Using simulated imaging of radio coronal mass ejections, we provide practical recommendations for the performance of radioheliographs. This study provides important support for the validation and calibration of radioheliograph data processing, and is expected to profoundly enhance our understanding of solar activities.
分类: 核科学技术 >> 粒子加速器 提交时间: 2023-06-18 合作期刊: 《Nuclear Science and Techniques》
摘要: In this paper, in order to achieve the output signal processing of cavity beam position monitor (CBPM), we develop a digital intermediate frequency receiver architecture based signal processing system, which consists of radio frequency (RF) front end and high speed data acquisition board. The beam position resolution in the CBPM signal processing system is superior to 1 m. Two signal processing algorithms, fast Fourier transform (FFT) and digital down converter (DDC), are evaluated offline using MATLAB platform, and both can be used to achieve, the CW input signal, position resolutions of 0.31 m and 0.10 m at 16 dBm. The DDC algorithm for its good compatibility is downloaded into the FPGA to realize online measurement, reaching the position resolution of 0.49 m due to truncation error. The whole system works well and the performance meets design target.