SOFTWARE FOR ADAPTING DSPZ RECEIVERS TO THE URAN INTERFEROMETER NETWORK

Анотація

More than 10 years ago, URAN interferometer  network  (Megn  A.V.,1997;  Konovalenko  A.A., 2014)  had  been  equipped  with  newly  designed  receivers with a pass band extended up to 250 kHz and software rejection of interferences (Rashkovskii, 2012). The broadening of bandwidth of received signal increase the sensitivity of  the  receivers  significantly  and  let  us  to  investigate  the angular structure about one hundred radio sources. A software package had been developed that allows: preparing a program  of  observations,  carrying  out  observations  automatically, making data cross-correlation, calculating visibility functions for all pairs of antennae, and fitting models of an  angular  structure  of  the  sources.  Data  storage  formats were elaborated for each stage of recording or processing. At present, new digital radio astronomy receiver DSPZ have been developed by IRA NASU (Zakharenko, 2016). The  receiver  allows  recording  an  entire  bandwidth  of  signals of a decameter range from 8 to 32 MHz. It is used at UTR-2  and  URAN  radio  telescopes  operated  in  a  single dish  mode.  Application of the receivers  for interferometer observation  with  the  URAN  network  provides  additional advantages  in  accuracy  and  sensitivity  of  studies.  In  this report  we  consider  the  data  formats  and  synchronization methods  used  in  URAN  equipment  and  DSPZ  receivers, and  discuss  algorithms  of  their  transformation.  Newly elaborated software is described, that allows selecting a set of  frequency  bands  of  signals  recorded  with  DSPZ  and converting them to the form used by the URAN software. This approach allows us to carry out the interferometer observations in an the extended frequency range provided by DSPZ and to use as much as possible the software package developed for the URAN network for data reduction.