VLBI@home - VLBI Correlator by GRID Computing System

摘要

Kashima VLBI group have been developing a VLBI software correlator system using GRID computing technology. Like SETI@home, client/server model is used in the system and screensaver-type correlator program runs only when the client PC is idle. No expensive dedicated hardware correlator is necessary, but standard personal computers in observatories provide CPU resources. Using software correlator system, the type of a correlation process is selectable (e.g. XF or FX, geodetic purpose or astronomical purpose) and correlation processes can be easily repeated, changing various kind of correlation parameters (e.g. integration time, phase center of the map, number of lags, FFT size). Current processing speed of the system has reached 70 Mbps by using sixteen low-cost PCs. The processing speed has been improving day by day, by means of algorithm improvements for the correlation program and installations of high-speed network equipments. This paper describes the configuration of the system in detail and reports on a first experimental result of GRID computing in VLBI.