In this research, we propose an adaptive symbol equalizer based on the least mean squares (LMS) algorithm to effectively handle inter-symbol interference arising in the modulation and demodulation processes of a software-defined radio (SDR)-based digital communication system.
The proposed algorithm applies training bits, recycled from sequence code bits according to existing modulation types like M-QAM, in the modulation and demodulation process. It optimizes based on minimizing errors through an iterative process involving the input training bits and the received bits.
The adaptive equalizer is capable of robustly and adaptively optimizing the shift and drift of symbols that occur in the M-QAM modulation and demodulation process.
The demonstration video for this can be viewed on the YouTube channel: LMS-based adaptive equalizer (Simulator based on NI).