A simplified, highly accurate, and real-time constellation pattern recognition and classification device for a software-defined communications apparatus is provided. The constellation pattern recognition and classification device includes an r(k) input, a group of test functions, a means for estimating, a means for calculating, a means for selecting the optimal test function, a means for signal processing, and a means for classifying a pattern that substantially decreases the amount of current constellation pattern calculations and intensive computational requirements and provides a real-time rapid response that improves performance of the software-defined communications apparatus. The present invention also includes a simplified, highly accurate, and real-time constellation pattern recognition and classification article of manufacture with a storage medium encoded with machine-readable computer program code for a software-defined communications system and a method for highly accurate and real-time reduced complexity constellation pattern recognition and classification for a software-defined communications system.