Automatic Modulation Classification: Principles, Algorithms and Applications

10Modulation Classifier Design for Military Applications

10.1 Introduction

The primary purpose of modulation classification in military scenarios is to ascertain information about an adversary by intercepting radiated energy. The detection and subsequent identification of the signal modulation have three possible uses. First, the knowledge of the modulation scheme can be directly used for the identification of the unit transmitting the signal. Secondly, if decryption and translation is added to the rear end of the modulation classifier and the demodulator, the transmitted message can be recovered if the modulation scheme can be classified. Thirdly, when jammers are deployed to disrupt transmission between adversary units, modulation classification is required to match the modulation of jamming signals and adversary signals.

Jamming is an important part of the electronic attack strategy (Poisel, 2008). The purpose is to override the adversary’s communication by introducing a man-made signal in the same communication channel. As the adversary receivers are matched with the transmitter, only the signal of the matching property will be picked up by the adversary receiver. In practice, a jamming signal must be transmitted using the same modulation technique and have the same carrier frequency. In addition, to override the adversary communication, the jamming signal must have higher power to hide the intended transmission. For a modulation classifier, the presence of a jamming signal ...