METHOD FOR THE PRE-DETECTION OF REPLIES IN A SECONDARY RADAR AND USE THEREOF IN THE DETECTION OF MODE S REPLIES

摘要

The invention relates to a method for the pre-detection of replies in a secondary radar. The invention can more particularly be used in the detection of mode S replies. One aim of the invention is to treat signals received prior to the decoding of the replies in order to enable the detection of mixed replies and to avoid detection of ghost replies. The invention relates in particular to a method for the pre-detection of replies in a secondary radar, wherein the replies to be pre-detected comprise a message coded by a modulated signal, characterized in that (1) the presence of a signal exhibiting modulation characteristics in line with those of a message of a reply to be pre-detected is identified; (ii) the duration of the identified signal is measured; (iii) said duration is compared to a minimum duration which is determined according to the duration of the messages of the replies that are to be pre-detected.