Alternative Signal Waveform Models for Advanced Interference Mitigation in 5G New Radio Systems

Abstract

The need for alternative signal waveforms to further cushion interference and increase transmission efficiency has been a challenge posed for researchers. With this in mind, this research developed two modified waveforms using Kaiser Windowed (KW) and Dolph-Chebyshev Windowed (DW) algorithms in a programmable Closed Loop Transfer Function (CLTF) digital module incorporated in a Hanning Windowed (HW) induced Filtered-Orthogonal Frequency Division Multiplexing (F-OFDM) system. This formed two alternative waveforms: Hann-Haiser Windowed F-OFDM (HKW-FOFDM) and Hann-Dolph Windowed F-OFDM (HDW-FOFDM). Simulation results taken at 120 kHz Subcarrier Spacing (SCS) showed the HKW-FOFDM system obtained an Advanced Interference Mitigation (AIM) of -30.83 dBm for Adjacent Channel Interference (ACI), -54.33 dBm for Inter-Symbol Interference (ISI), and -53.70 dBm for Inter-Channel Interference (ICI), which amounted to an improvement of 28.28%, 24.95%, and 31.10% over those obtained by the HW-FOFDM system, respectively. Similarly, the HDW-FOFDM achieved an AIM of -34.33 dBm for ACI, -44.00 dBm for ISI, and -51.17 dBm for ICI, which resulted in an improvement of 45.05%, 21.98%, and 24.98% over those obtained by the HW-FOFDM system, respectively. The developed waveforms have the added advantage of increasing bandwidth by virtue of AIM.  This has proven its capability in driving different 5G New Radio (NR) numerologies of 0 to 3 by increasing the system’s scalability.