I. Introduction
Simultaneous localization and communications(SLAC) becomes a new feature in the fifth-generation (5G) and beyond cellular networks. This technique can facilitate various applications, such as Internet-of-Things (IoTs) and autonomous driving [1]. The bridge between the localization and communications is the propagation channel, which is used for data transfer while carrying position-dependent information. Typical channel parameters with position dependence include the received signal strength (RSS), time of arrival (ToA), angle of arrival (AoA), Doppler shift, and others. The acquisition of these parameters is dependent on the physical layer signal design and processing of the communications systems.