Design of a multi-function high-speed digital baseband data acquisition system

• Published in: 天文和天体物理学研究 Vol. 21; no. 10; pp. 61 - 72
• Main Authors: Xin Pei, Jian Li, Na Wang, Toktonur Ergesh, Xue-Feng Duan, Jun Ma, Mao-Zheng Chen
• Format: Journal Article
• Language: English
• Published: Xinjiang Key Laboratory of Microwave Technology,Urumqi 830011,China%Xinjiang Astronomical Observatory,Chinese Academy of Sciences,Urumqi 830011,China 2021; University of Chinese Academy of Sciences,Beijing 100049,China; Xinjiang Astronomical Observatory,Chinese Academy of Sciences,Urumqi 830011,China; Key Laboratory of Radio Astronomy,Chinese Academy of Sciences,Nanjing 210008,China
• Subjects: instrumentation:miscellaneous; techniques:miscellaneous; site testing
• ISSN: 1674-4527; 2397-6209
• DOI: 10.1088/1674-14527/21/10/248

A multi-function digital baseband data acquisition system is designed for the sampling,distribution and recording of wide-band multi-channel astronomical signals.The system hires a SNAP2 board as a digital baseband converter to digitize,channelize and packetize the received signal.It can be configured dynamically from a single channel to eight channels with a maximum bandwidth of 4096 MHz.Eight parallel HASHPIPE instances run on four servers,each carrying two NVMe SSD cards,achieving a total continuous write rate of 8 GB s-1.Data are recorded in the standard VDIF file format.The system is deployed on a 25-meter radio telescope to verify its functionality based on pulsar observations.Our results indicate that during the 30-minute observation period,the system achieved zero data loss at a data recording rate of 1 GB s-1 on a single server.The system will serve as a verification platform for testing the functions of the QTT(QiTai radio Telescope)digital backend system.In addition,it can be used as a baseband/VLBI(Very Long Baseline Interferometry)recorder or D-F-engine of correlator/beamformer as well.