Performance Comparison of Adaptive Modulation and Coding in OFDM Systems Using Signalling and Automatic Modulation Classification

Abstract:
This paper compares the system performance of signalling and automatic modulation classification in adaptive orthogonal frequency division multiplexing (OFDM)- based systems in time-division duplex (TDD) mode. In previous theoretical contributions, transmitter-side joint adaptive modulation and coding (AM+C) techniques have been proposed which can be used to either increase the data rate or, alternatively, improve the link reliability. Since the receiver must be synchronized to the transmit parameters, the required signalling overhead reduces the benefit of adaptive modulation and coding when applied to practical systems. Numerical results in terms of the effective data bandwidth efficiency reveal the potential of recently developed automatic modulation classifiers as an alternative to conventional signalling schemes. Index Terms — OFDM, adaptive modulation and coding, automatic modulation classification, signalling