Performance of a novel fast transients detection system
We investigate the signal-to-noise ratio (S/N) of a new incoherent dedispersion algorithm optimized for FPGA-based architectures intended for deployment on the Australian SKA Pathfinder and other Square Kilometre Array precursors for fast transients surveys. Unlike conventional CPU- and GPU-optimize...
| Main Authors: | , , |
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| Format: | Journal Article |
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Institute of Physics Publishing, Inc.
2013
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| Online Access: | http://hdl.handle.net/20.500.11937/29566 |
| _version_ | 1848752838419677184 |
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| author | Clarke, Nathan Macquart, Jean-Pierre Trott, Cathryn |
| author_facet | Clarke, Nathan Macquart, Jean-Pierre Trott, Cathryn |
| author_sort | Clarke, Nathan |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | We investigate the signal-to-noise ratio (S/N) of a new incoherent dedispersion algorithm optimized for FPGA-based architectures intended for deployment on the Australian SKA Pathfinder and other Square Kilometre Array precursors for fast transients surveys. Unlike conventional CPU- and GPU-optimized incoherent dedispersion algorithms, this algorithm has the freedom to maximize the S/N by way of programmable dispersion profiles that enable the inclusion of different numbers of time samples per spectral channel. This allows, for example, more samples to be summed at lower frequencies where intra-channel dispersion smearing is larger, or it could even be used to optimize the dedispersion sum for steep spectrum sources. Our analysis takes into account the intrinsic pulse width, scatter broadening, spectral index and dispersion measure of the signal, and the system's frequency range, spectral and temporal resolution, and number of trial dedispersions. We show that the system achieves better than 80% of the optimal S/N where the temporal resolution and the intra-channel smearing time are smaller than a quarter of the average width of the pulse across the system's frequency band (after including scatter smearing). Coarse temporal resolutions suffer a Δt –1/2 decay in S/N, and coarse spectral resolutions cause a Δv–1/2 decay in S/N, where Δt and Δv are the temporal and spectral resolutions of the system, respectively. We show how the system's S/N compares with that of matched filter and boxcar filter detectors. We further present a new algorithm for selecting trial dispersion measures for a survey that maintains a given minimum S/N performance across a range of dispersion measures. |
| first_indexed | 2025-11-14T08:14:59Z |
| format | Journal Article |
| id | curtin-20.500.11937-29566 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T08:14:59Z |
| publishDate | 2013 |
| publisher | Institute of Physics Publishing, Inc. |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-295662017-09-13T15:26:48Z Performance of a novel fast transients detection system Clarke, Nathan Macquart, Jean-Pierre Trott, Cathryn methods detectors radio continuum observational surveys pulsars instrumentation general We investigate the signal-to-noise ratio (S/N) of a new incoherent dedispersion algorithm optimized for FPGA-based architectures intended for deployment on the Australian SKA Pathfinder and other Square Kilometre Array precursors for fast transients surveys. Unlike conventional CPU- and GPU-optimized incoherent dedispersion algorithms, this algorithm has the freedom to maximize the S/N by way of programmable dispersion profiles that enable the inclusion of different numbers of time samples per spectral channel. This allows, for example, more samples to be summed at lower frequencies where intra-channel dispersion smearing is larger, or it could even be used to optimize the dedispersion sum for steep spectrum sources. Our analysis takes into account the intrinsic pulse width, scatter broadening, spectral index and dispersion measure of the signal, and the system's frequency range, spectral and temporal resolution, and number of trial dedispersions. We show that the system achieves better than 80% of the optimal S/N where the temporal resolution and the intra-channel smearing time are smaller than a quarter of the average width of the pulse across the system's frequency band (after including scatter smearing). Coarse temporal resolutions suffer a Δt –1/2 decay in S/N, and coarse spectral resolutions cause a Δv–1/2 decay in S/N, where Δt and Δv are the temporal and spectral resolutions of the system, respectively. We show how the system's S/N compares with that of matched filter and boxcar filter detectors. We further present a new algorithm for selecting trial dispersion measures for a survey that maintains a given minimum S/N performance across a range of dispersion measures. 2013 Journal Article http://hdl.handle.net/20.500.11937/29566 10.1088/0067-0049/205/1/4 Institute of Physics Publishing, Inc. fulltext |
| spellingShingle | methods detectors radio continuum observational surveys pulsars instrumentation general Clarke, Nathan Macquart, Jean-Pierre Trott, Cathryn Performance of a novel fast transients detection system |
| title | Performance of a novel fast transients detection system |
| title_full | Performance of a novel fast transients detection system |
| title_fullStr | Performance of a novel fast transients detection system |
| title_full_unstemmed | Performance of a novel fast transients detection system |
| title_short | Performance of a novel fast transients detection system |
| title_sort | performance of a novel fast transients detection system |
| topic | methods detectors radio continuum observational surveys pulsars instrumentation general |
| url | http://hdl.handle.net/20.500.11937/29566 |