An accurate and efficient algorithm for detection of radio bursts with an unknown dispersion measure, for single dish telescopes and interferometers

Abstract

Astronomical radio bursts disperse while traveling through the interstellar medium. To optimally detect a short-duration signal within a frequency band, we have to precisely compensate for the pulse dispersion, which is a computationally demanding task. We present the Fast Dispersion Measure Transform (FDMT) algorithm for optimal detection of such signals. Our algorithm has a low theoretical complexity of 2N_f N_t+ N_t N_d log_2(N_f) where N_f, N_t and N_d are the numbers of frequency bins, time bins, and dispersion measure bins, respectively. Unlike previously suggested fast algorithms our algorithm conserves the sensitivity of brute force dedispersion. Our tests indicate that this algorithm, running on a standard desktop computer, and implemented in a high-level programming language, is already faster than the state of the art dedispersion codes running on graphical processing units (GPUs). We also present a variant of the algorithm that can be efficiently implemented on GPUs. The latter algorithm's computation and data transport requirements are similar to those of two-dimensional FFT, indicating that incoherent dedispersion can now be considered a non-issue while planning future surveys. We further present a fast algorithm for sensitive dedispersion of pulses shorter than normally allowed by incoherent dedispersion. In typical cases this algorithm is orders of magnitude faster than coherent dedispersion by convolution. We analyze the computational complexity of pulsed signal searches by radio interferometers. We conclude that, using our suggested algorithms, maximally sensitive blind searches for such pulses is feasible using existing facilities. We provide an implementation of these algorithms in Python and MATLAB.

Submitted to ApJ. Comments and suggestions are welcome!

References in corpus (6)

• A bright millisecond radio burst of extragalactic origin
• A Population of Fast Radio Bursts at Cosmological Distances
• Fast radio bursts: search sensitivities and completeness
• Temporal Smearing of Transient Radio Sources by the Intergalactic Medium
• Pulse Broadening Measurements from the Galactic Center Pulsar J1745--2900
• An absence of fast radio bursts at intermediate galactic latitudes

Cited by in corpus (35)

• Fast Radio Bursts
• A single fast radio burst localized to a massive galaxy at cosmological distance
• Observations of Protoplanetary Disk Structures
• The CHIME Fast Radio Burst Project: System Overview
• Fast Radio Burst 121102 Pulse Detection and Periodicity: A Machine Learning Approach
• The detection of an extremely bright fast radio burst in a phased array feed survey
• Faint Repetitions from a Bright Fast Radio Burst Source
• Applying Deep Learning to Fast Radio Burst Classification
• Chronicling the Host Galaxy Properties of the Remarkable Repeating FRB 20201124A
• BURSTT: Bustling Universe Radio Survey Telescope in Taiwan
• Optimal and Efficient Streak Detection in Astronomical Images
• The Commensal Real-time ASKAP Fast Transient incoherent-sum survey
• Real-Time Dedispersion for Fast Radio Transient Surveys, using Auto Tuning on Many-Core Accelerators
• Searching for giga-Jansky fast radio bursts from the Milky Way with a global array of low-cost radio receivers
• Single Pulse Detection Algorithms for Real-time Fast Radio Burst Searches using GPUs
• A Survey of the Galactic Plane for Dispersed Pulses with the Australian Square Kilometre Array Pathfinder
• The Performance and Calibration of the CRAFT Fly's Eye Fast Radio Burst Survey
• A search for FRB 121102-like persistent radio-luminous sources -- Candidates and implications for the FRB rate and searches
• PulsarX: a new pulsar searching package -I. A high performance folding program for pulsar surveys
• A Southern sky search for repeating Fast Radio Bursts using the Australian SKA Pathfinder
• A multi-epoch, multi-wavelength study of the classical FUor V1515 Cyg approaching quiescence
• Systematic performance of the ASKAP Fast Radio Burst search algorithm
• The Application of Autocorrelation SETI Search Techniques in an ATA Survey
• Galactic Radio Explorer: an all-sky monitor for bright radio bursts
• The CRAFT Coherent (CRACO) upgrade I: System Description and Results of the 110-ms Radio Transient Pilot Survey
• Formation of trans-Neptunian satellite systems at the stage of condensations
• fBLS -- a fast-folding BLS algorithm
• The impact of the FREDDA dedispersion algorithm on $H_0$ estimations with FRBs
• Modeling the Vertical Structure of Nuclear Starburst Discs: A Possible Source of AGN Obscuration at $z\sim 1$
• Fourier-domain dedispersion
• A Radio Burst Detection Method Based on the Hough Transform
• Accelerating Dedispersion using Many-Core Architectures
• SPARKESX: Single-dish PARKES data sets for finding the uneXpected -- A data challenge
• Comparison of Fast, Hybrid Imaging Architectures for Multi-scale, Hierarchical Aperture Arrays
• Detecting FRB by DANCE: a method based on DEnsity ANalysis and Cluster Extraction