Wideband operation

  When it is necessary to observe more than 920 MHz of bandwidth simultaneously, the wideband option can be selected when the DAS is loaded. Note that currently only RxC2 gives sufficient bandwidth to utilise this mode. The IF switch splits the the signal into two 1 GHz channels at the receiver output and sends these down IF channels 1 and 2, into the DAS inputs A0 and B0. This gives 2 920 MHz or 1800 MHz of bandwidth, approximately 1600 MHz of which is currently useable (see Figure 5).

In SPECX, the two halves are stored in the X and Y registers. To reduce, run das-merge on each half separately, combine them with the @combine command, then merge the data to get the full bandwidth in one spectrum.