The effect of signal digitisation in CMB experiments
arXiv:astro-ph/0304089 · doi:10.1051/0004-6361:20031489
Abstract
Signal digitisation may produce significant effects in balloon - borne or space CMB experiments, since the limited bandwidth for downlink of data requires imposes a large quantisation step q applied on board by the instrument acquisition chain. In this paper we present a study of the impact of the quantization error in CMB experiments using, as a working case, simulated data from the Planck/LFI. At TOD level, the effect of the quantization can be approximated as a source of nearly normally distributed noise. At map level, the data quantization alters the noise distribution and the expectation of some higher order moments. Finally, at the levell of power spectra, the quantization introduces a power excess, that, although related to the instrument and mission parameters, is weakly dependent on the multipole l at middle and large l and can be quite accurately subtracted, leaving a residual uncertainty of few % of the RMS uncertainty. Only for l<30 the quantization removal is less accurate.
15 pages, 5 figures, LaTeX2e, A&A style (aa.cls). Release 1, april 1st 2003. Submitted to A&A for the pubblication, april 1st 2003. Contact author: [email protected]
References in corpus (12)
- A Flat Universe from High-Resolution Maps of the Cosmic Microwave Background Radiation
- 4-Year COBE DMR Cosmic Microwave Background Observations: Maps and Basic Results
- Cosmological Parameter Extraction from the First Season of Observations with DASI
- Extragalactic Source Counts and Contributions to the Anisotropies of the Cosmic Microwave Background. Predictions for the Planck Surveyor mission
- Power Spectrum of Primordial Inhomogeneity Determined from the 4-Year COBE DMR Sky Maps
- First Intrinsic Anisotropy Observations with the Cosmic Background Imager
- All-sky astrophysical component separation with Fast Independent Component Analysis (FastICA)
- 1/f noise and other systematic effects in the Planck-LFI radiometers
- The Planck-LFI instrument: analysis of the 1/f noise and implications for the scanning strategy
- Information content in Gaussian noise: optimal compression rates
- Data Streams from the Low Frequency Instrument On-Board the Planck Satellite: Statistical Analysis and Compression Efficiency
- Data Processing and Compression of Cosmic Microwave Background Anisotropies on Board the PLANCK Satellite