Algorithms and formulas for hybrid correlator data correction Abs.

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ALMA Memo # 583


Algorithms and formulas for hybrid correlator data correction

Giovanni Comoretto

2008-11-05

This report describes the algorithms and formulas used to reconstruct the hybrid auto or cross spectra from the ALMA correlator output. This process includes the quantization correction ("Van Vleck correction") for the 2 bit quantization, Fourier Transform, calibration for tunable flter passband response and for different amplitude among sub-channels, stitching of the sub-channel spectra in a single composite spectrum, and final correction for the sampler 3-bit quantization. The final product consists in normalized ACF and CCF spectra, processed and presented in a consistent and uniform way for all correlation modes.

View a pdf version of ALMA Memo #583.

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