Output Rate

Correlation parameters should result in an output rate less than 10 MBytes per second (of observing time) for routine DiFX processing; higher rates may be considered if required and adequately justified. Observers should ensure that their data-analysis facilities can handle the dataset volumes that will result from the correlation parameters they specify.

An approximate parametrization of the output rate is given by

\[R = 4 \cdot \frac{N_{\rm stn} \cdot (N_{\rm stn}+1) \cdot N_{\rm sbb} \cdot N_{\rm spc}}{T_{\rm int}}\cdot N_{\rm ppb} \cdot N_{\rm phc} \cdot p\]

where the rate \(R\) is in Byte/s;

\( N_{\rm stn} , \; N_{\rm sbb} , \; N_{\rm spc} \) are the numbers of observing stations, data channels, and spectral points per data channel, respectively;

\(T_{\rm int}\) is the correlator integration period;

\(N_{\rm ppb}\) is the number of pulsar phase bins;  and

\(N_{\rm phc}\) is the number of phase centers.

The polarization factor \(p=1\) for single-polar, or dual-polar parallel-hand output;  or \(p=2\) for cross-polar, four-Stokes processing.

Output data rates are also estimated by SCHED.

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