The Breakthrough Listen Search for Intelligent Life: A Wideband Data Recorder System for the Robert C. Byrd Green Bank Telescope

Abstract

The Breakthrough Listen Initiative is undertaking a comprehensive search for radio and optical signatures from extraterrestrial civilizations. An integral component of the project is the design and implementation of widebandwidth data recorder and signal processing systems. The capabilities of these systems, particularly at radio frequencies, directly determine survey speed; further, given a fixed observing time and spectral coverage, they determine sensitivity as well. Here, we detail the Breakthrough Listen wide-bandwidth data recording system deployed at the 100 m aperture Robert C. Byrd Green Bank Telescope. The system digitizes up to 6 GHz of bandwidth at 8 bits for both polarizations, storing the resultant 24 GB s −1 of data to disk. This system is among the highest data rate baseband recording systems in use in radio astronomy. A future system expansion will double recording capacity, to achieve a total Nyquist bandwidth of 12 GHz in two polarizations. In this paper, we present details of the system architecture, along with salient configuration and disk-write optimizations used to achieve high-throughput data capture on commodity compute servers and consumer-class hard disk drives.

A fast radio burst with frequency-dependent polarization detected during Breakthrough Listen observations

“…While the BL survey follows a similar observational strategy to the HTRU and SUrvey for Pulsars and Extragalactic Radio Bursts (SUPERB) surveys , technosignature searches require a far higher spectral resolution (∼ 1 Hz, Siemion et al 2015) than that available in archival data products from the HTRU/SUPERB surveys (∼ 390 kHz). As such, new digital recorder systems have been installed at both the Parkes and Green Bank observatories to allow voltage capture to disk across the full bandwidth of the available receivers (MacMahon et al 2018;Price et al 2018a).…”

The Breakthrough Listen search for intelligent life: Wide-bandwidth digital instrumentation for the CSIRO Parkes 64-m telescope

“…BLPDR is a heterogeneous digital signal processing (DSP) system that digitizes the signal from the telescope, records data to disk, and performs DSP tasks for data analysis and reduction. The overall architecture of the BLPDR system is comparable with that of the BL data recorder system installed at Green Bank (MacMahon et al, 2018): a field-programmable gate array (FPGA) signal processing 'frontend' is connected via high-speed Ethernet to a signal processing 'backend' consisting of compute servers equipped with graphics processing units (GPUs). System monitor and control is carried out via a 'head node' server, which also interfaces with the Parkes telescope control systems to collect observation metadata.…”

“…In this article, we report on the Breakthrough Listen data recorder system for Parkes (BLPDR); the BL digital systems for the Green Bank telescope are detailed in MacMahon et al (2018). The BLPDR system is designed to digitize, record and process the entire ∼4.3 GHz aggregate bandwidth provided by the the 21-cm multibeam, and similarly the entire ∼1 GHz of bandwidth provided by the single beam conversion system.…”

Interstellar communication: Short pulse duration limits of optical SETI

“…The data stream is then 100 GB s −1 . For comparison, the Breakthrough Listen Radio Data Recorder (MacMahon et al 2018) saves 24 GB s −1 of data to disk. Their computing facilities also allow for real-time de-dispersion and pulse search.…”