Coexistence of Filter Banks and CP-OFDM: What are the Real Gains?

TL;DR

This paper critically examines the coexistence of filter bank waveforms with legacy CP-OFDM systems, revealing that previous claims of high spectral efficiency are based on incorrect interference metrics, and demonstrating that FB waveforms interfere more than previously thought.

Contribution

The study shows that existing interference metrics are flawed and provides new insights into the actual interference levels of FB waveforms with CP-OFDM, challenging prior optimistic assessments.

Findings

FB waveforms interfere significantly with CP-OFDM receivers.

Previous studies overestimated the spectral efficiency of FB waveforms.

Incorrect interference metrics led to overly optimistic conclusions.

Abstract

A coexistence scenario between filter bank (FB) based waveforms and legacy Cyclic Prefix-Orthogonal Frequency Division Multiplexing (CP-OFDM) is studied. It is shown that studies available on that matter use a wrong metric to rate the interference between the coexisting systems. Specifically, it is shown that even well spectrally localized FB waveforms interfere at a high level with incumbent CP-OFDM receivers. The presented results invalidate a number of studies in the literature, which stated that FB based waveforms could be very efficiently used to insert communications in parts of spectrum left free by incumbent legacy CP-OFDM users.