Thursday, June 28, 2007

fruitful day!

things done:

  1. AIPS processing tutorial by Chiranjeevi, it has given a new perspective about GMRT interference removal and calibration.

  2. ms for SAX 1808 paper is ready for desh's view.

  3. there has been tons of discussion about radio telescope.

    • the 2-bit samples from 4 elements could combined in one byte per sample rate.

    • Cross-correlations of each two-element pairs (total 6 pairs, called 'baselines') can be done for N delays. Resultant array of N correlations can be passed over to FFT, resulting in amplitudes and phases for N/2 spectral channels. (This job can be simplified by using tabulated results for all 8-byte combinations).

    • The value N above is decided by delta-u and delta-v that we can have, using 1/imsize for our map (possibly 1/60 deg).

    • We need to keep computing such cross-correlations over a large time, integrating amplitude and phases over a large time (about 8 seconds or so).

    • These integrated amp and phases are the output (dynamic spectrum) of an effective software correlator.

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