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http://dx.doi.org/10.5303/PKAS.2016.31.2.011

A STUDY ON THE RELIABILITY OF THE DAEJEON HARDWARE CORRELATOR FOR THE KVN OBSERVATION MODES  

OH, SE-JIN (Korea Astronomy and Space Science Institute)
ROH, DUK-GYOO (Korea Astronomy and Space Science Institute)
YEOM, JAE-HWAN (Korea Astronomy and Space Science Institute)
OH, CHUNG-SIK (Korea Astronomy and Space Science Institute)
LEE, SANG-SUNG (Korea Astronomy and Space Science Institute)
JUNG, DONG-KYU (Korea Astronomy and Space Science Institute)
KIM, HYO-RYOUNG (Korea Astronomy and Space Science Institute)
CHUNG, HYUN-SOO (Korea Astronomy and Space Science Institute)
Publication Information
Publications of The Korean Astronomical Society / v.31, no.2, 2016 , pp. 11-19 More about this Journal
Abstract
This paper presents the results of test observations toward a point source, 4C39.25, for observation modes with various bandwidths and numbers of IF streams in order to examine a reliability of the Daejeon hardware correlator performance for correlating VLBI (Very Long Baseline Interferometry) data obtained with the several observation modes of the KVN (Korean VLBI Network). We used a DiFX software correlator (DiFX) as a reference, for investigating the output visibilities from the Daejeon corelator. It is found that the band shapes of the output visibilities from two correlators are similar to each other and the correlated flux density for each baseline obtained from the Daejeon hardware correlator is lower by 3 - 7% than that from the DiFX. The flux difference is attributed to the limitation of FPGA resources and the difference of fringe rotation algorithm of the Daejeon hardware correlator. The conversion factor, 0.93 ~ 0.97, is proposed for future correlation with the Daejeon hardware correlator.
Keywords
Daejeon hardware correlator; Observation mode; Wide and Narrow band;
Citations & Related Records
Times Cited By KSCI : 3  (Citation Analysis)
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