OFDM and FBMC Spectral Properties Comparison in Narrow-Band Channels

The paper provides a comprehensive analysis comparing the spectral properties of two prominent multicarrier modulation techniques: Orthogonal Frequency Division Multiplexing (OFDM) and Filter Bank Multi-Carrier (FBMC). This comparison is specifically contextualized for narrow-band channel environments, where efficient spectrum utilization and minimal out-of-band emissions are critical. OFDM has been widely adopted in current wireless standards including 5G, while FBMC has emerged as a promising candidate for 6 G and beyond due to its improved spectral characteristics, particularly relevant for narrow-band applications. The comparative analysis reveals that FBMC offers significantly better spectral containment through persubcarrier filtering and elimination of cyclic prefix overhead, which is a key advantage in narrow-band scenarios. Additionally, the paper explores how Offset Quadrature Amplitude Modulation (OQAM) enables FBMC to maintain orthogonality without cyclic prefix and examines the impact of different prototype filters on spectral efficiency. Furthermore, the research proposes a methodology using Welch’s power spectral density estimation technique to quantitatively compare OFDM and FBMC performance through MATLAB simulations. This work identifies research gaps in practical implementation considerations and standardized comparison frameworks for next-generation modulation schemes, especially concerning their suitability for narrow-band wireless systems.