Spectral detector for interference time blanking using quantized correlator

¹ LESI-ESPEO, Université d'Orléans, 45000 Orléans, France
² ETIS-ENSEA, 95000 Cergy-Pontoise, France
³ Unité Scientifique de Nançay, Observatoire de Paris, 1 Place Jules Janssen, F-92195 Meudon Principal Cedex, France
⁴ GTR-IUT de Blois, 41 000 Blois, France

Send offprint request to: R. Weber

Received: 10 December 1996
Accepted: 21 February 1997

Abstract

Given the large flow of data to be processed, quantized correlators are widely used in radio astronomy. Unfortunately, the occurrence of non-Gaussian interference combined with a coarse quantization can strongly alter the shape of the estimated spectra. The final spectral estimation can be preserved by blanking the correlator in real-time. A new interference detection criterion is proposed within this framework. It uses the real-time capabilities of correlators and compares contaminated and non-contaminated correlation functions. No a priori information on the interfering signals is required. Simulations, using synthetic and actual data, are presented. This new technique of real time detection can significantly improve the quality of spectral line observations.