I. Introduction
Fifth generation (5G) wireless networks are under deployment and the basic functionalities and capabilities are defined within the 5G standard [2]. However, there still exist many requirements that 5G networks may not satisfy, and sixth generation (6G) wireless networks are envisioned to offer seamless and ubiquitous coverage, higher communication capability and sensing/localization precision, and enhanced intelligence and security level, etc., [2], [3], [4], [5], and [6]. One of the potential application scenarios of 6G networks is the integrated communications and localization (ICAL) on Internet of Everything (IoE), including tracking of persons or robots in an industrial site, autonomous driving, emergency response, etc. In such use cases, communications and localization are simultaneously performed by jointly designing the signal waveform for shared spectrum on one hardware platform, to improve the utilization of resources [2], [5].