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A Study on Solving of Double-layer Pattern Problem in Daejeon Correlator  

Oh, Se-Jin (한국천문연구원)
Roh, Duk-Gyoo (한국천문연구원)
Yeom, Jae-Hwan (한국천문연구원)
Chung, Dong-Kyu (한국천문연구원)
Oh, Chung-Sik (한국천문연구원)
Hwang, Ju-Yeon (한국천문연구원)
Publication Information
Journal of the Institute of Convergence Signal Processing / v.16, no.4, 2015 , pp. 162-167 More about this Journal
Abstract
This paper describes the reason and the problem solving for the double-layer pattern of a Daejeon correlator operated in Korea-Japan Correlation Center. When the electric power of an input signal in the correlator is charged small enough to be buried in the noise, it is hard to see a signal with a specific pattern in the input signal, but when the electric power is large, a specific one is reported to be seen. By comparing data from observation with one from software correlator, it was confirmed from the analysis using the AIPS software that the amplitude gain of a source signal was affected about 3%. Therefore, in order to solve the problem of double-layer patterns, we found that a problem in the memory management module responsible for both the data input and the data serialization of the correlator is a cause for the double-layer pattern detected periodically. In other words, while data is serialized and read repeatedly in the memory area assigned to serialize the data from the serialization module, redundant last data is generated and an overlap for the memory allocation is occurred. Therefore, by modifying the program of the FPGA memory sections on serialization module to correct the problem, we confirmed that double-layer pattern is disappeared and correlation results are normally acquired.
Keywords
Double-layer Pattern; Data Serialize Memory Map; Daejeon Correlator;
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Times Cited By KSCI : 1  (Citation Analysis)
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