The design and implementation of a ROACH2+GPU based correlator on the Tianlai dish array

• 来源期刊: 天文和天体物理学研究
• 年，卷（期）: 2019,（7）
• 页码范围: 133-142
• 页数: 10页
• 语种: 英文
• DOI: 10.1088/1674-4527/19/7/102

摘要

A digital correlator is a crucial element in a modern radio telescope.In this paper,we describe a scalable design for the correlator system of the Tianlai pathfinder array,which is an experiment dedicated to testing key technologies for conducting a 21 cm intensity mapping survey.The correlator implements the FX design,which firstly performs a fast Fourier transform (FFT) including polyphase filter bank (PFB) computation using a Collaboration for Astronomy Signal Processing and Electronics Research (CASPER) Reconfigurable Open Architecture Computing Hardware-2 (ROACH2) board,then computes cross-correlations by employing Graphics Processing Units (GPUs).The design has been tested both in laboratory and in actual observation.