Method of processing a distorted signal of a MODE-S format from an airplane transponder

Abstract

The article describes a rather efficient method for processing a signal of the MODE-S format, which has distortions in amplitude and timing parameters. Distortion can be caused by various factors, such as the presence of interference in the air and the reflection of the signal, the impact of various electromagnetic fields. Receiving and further processing of the signal with distortion can not be performed correctly using simple algorithms that do not take into account these features. The method described below allows processing part of the distorted signals correctly and increasing the total number of decoded signals. MODE-S is part of a large air traffic processing and monitoring system. Today, a large number of civil aircraft are equipped with receivers and transponders of signal in MODE-S format. This system allows identifying aircraft and obtaining the necessary information about the flight in a simple way. MODE-S works on the question-answer principle. The so-called “question” is sent to the aircraft in order to obtain specific information about the flight. The aircraft accepts this “question”, analyzes its format and, depending on it, sends an “answer” back. It is very important to process correctly as many signals as possible, because the information in them is important and must be received on time.