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Abstract-It is well known that planet Jupiter produces strong radio bursts at decametric wavelengths from regions of temporary radio emission in its magnetosphere. Like the man made radio signals, these signals do interfere in the low frequency radio telescope data while observing a different extraterrestrial source. Identification and characterization of this interfering signal is important in radio astronomy. In most of the radio astronomy sites, spectrum monitoring stations are available for such purposes. These instruments record any strong signal within the band and also aim to locate its position. Depending on the properties of different categories of sources, special modules can be attached to these instruments for obtaining a more detailed picture. These modules can be added at the front end of the instrument using a selector switch and can be connected whenever necessary. Construction of one such module for capturing and recording the Jupiter radio bursts has been described with all the engineering details. It consists of an antenna system followed a receiver (connected to a spectrum recorder). An improvement in the antenna system has been made as compared to the contemporarily available single antenna Jupiter radio telescopes, thereby enabling to record the radio emissions over a larger period using a fixed beam. The receiver system has been designed to process the low frequency Jovian signals from 18 to 25 MHz. The back end is that of a spectrum monitoring system which serves as an automated data analyzer and 128 Joardar and Bhattacharya recorder. It offers flexibility and various setup choices to the user. The mathematical analysis of the instrument and computed system characteristics have been produced in detail for ease of reproductions, direct use in radio astronomy and future design developments.

Abstract-A prototype of dual polarized ultra wideband antenna-feed was fabricated (200 MHz-2000 MHz) for usage in low frequency radio astronomy at the GMRT (Giant Meterwave Radio Telescope). The feed was mounted on one of the GMRT dish antennas and tested using signals from the radio galaxy Cygnus A and zenith sky. Modeling of the GMRT dish with the antenna-feed mounted at its focus has been done. With the use of simulated radiation patterns of the antennafeed and the measured results, the system independent deflections at various frequencies were computed. The performances of the GMRT dish with present mesh and RMS (root mean square) efficiencies have been studied. Performance of the GMRT dish with 100% mesh and RMS efficiencies were computed. Future guidelines of ultra wideband antenna-feed design for GMRT have been indicated. Improvements of the GMRT dishes have also been suggested.