A low-noise, high-dynamic-range, digital receiver for radio astronomy applications: an efficient solution for observing radio-bursts from Jupiter, the Sun, pulsars, and other astrophysical plasmas below 30 MHz

V. B. Ryabov¹, D. M. Vavriv², P. Zarka³, B. P. Ryabov², R. Kozhin², V. V. Vinogradov² and L. Denis⁴

¹ Future University-Hakodate, 116-2 Kamedanakano-cho, Hakodate 041-8655, Japan e-mail: riabov@fun.ac.jp
² Institute of Radio Astronomy, 4 Krasnoznamennaya St, 610002 Kharkov, Ukraine
³ LESIA, Observatoire de Paris, CNRS, UPMC, Université Paris Diderot, 5 Place Jules Janssen, 92190 Meudon, France
⁴ Station de Radioastronomie, USN, Paris Observatory, 18330 Nançay, France

Received: 22 September 2009
Accepted: 4 November 2009

Abstract

A new two-channel digital receiver that can be used for observing both stationary and sporadic radio sources in the decameter wave band is presented. Current implementation of the device operating at the sampling frequency of 66 MHz is described in detail, including the regimes of waveform capture, spectrogram analysis, and coherence analysis (cross covariance between the two inputs). Various issues pertaining to observational methods in the decameter waveband affected significantly by man-made interferences have been taken into account in the receiver design, as well as in the architecture of the interactive software that controls the receiver parameters in real time. Two examples of using the receiver with the UTR-2 array (Ukraine) are reported: S-bursts from Jupiter and low-frequency wide-band single pulses from the pulsar PSR0809+74