Multirate 5G Downlink Performance Comparison for f-OFDM and w-OFDM Schemes with Different Numerologies

TL;DR

This paper compares the downlink performance of f-OFDM and w-OFDM schemes with different numerologies in 5G, highlighting their spectral efficiency and implementation trade-offs.

Contribution

It provides a comprehensive comparison of f-OFDM and w-OFDM with multiple numerologies, including multirate transmission considerations for 5G downlink.

Findings

f-OFDM reduces OOB emissions compared to traditional OFDM.

w-OFDM offers better spectral localization with windowing.

Multirate transmission with multiple numerologies is feasible and effective.

Abstract

One of the main open problems for next generation wireless networks, is to find the new OFDM-based waveform to be used in 5G. The new modulation scheme must primarily be able to achieve higher spectral efficiency than its predecessor. The main 3GPP's candidate is a new version of OFDM, called Filtered Orthogonal Frequency-Division Multiplexing (f-OFDM), which is similar to OFDM but with additional filtering in order to reduce Out-Of-Band (OOB) emissions and to obtain a better spectral-localization. Another option is windowed-OFDM (w-OFDM), which is basically a classical OFDM scheme where each symbol is windowed and overlapped in the time domain. In this paper we compare classic OFDM signals using Cyclic Prefix (CP-OFDM) with f-OFDM and w-OFDM, each one with multiple parametric options and numerologies. A multirate transmitter simultaneously operating with multiple numerologies is considered, where the transmitted sub-bands must be up-sampled and interpolated in order to generate the composite numerical signal fed to the Digital to Analog Converter (DAC). Finally, we discuss advantages and disadvantages of the various schemes.