Geometry-Enhanced 3GPP Multipath Channel Model for Bistatic ISAC Research

Wireless networks are currently being redesigned to provide localization, sensing, and communication services exploiting the same hardware, spectrum, and waveform. Many solutions addressing different aspects of the system design are being proposed, but standardized channel models suitable to evaluate the localization and sensing performances associated to these solutions are still lacking. In this paper, we propose an extension of the 3GPP channel model where the generated multipath components fulfill the physical properties exploited by localization and bistatic sensing algorithms. In particular, our channel model supports physically consistent first order reflections in a subset of the paths. The proposed channel model modifications are motivated by well established empirical observations about wireless multipath channels. The proposal follows an a-posteriori modification strategy: first the multiple paths are generated according to the standard statistical channel model, and afterwards some of them are converted to physically consistent first order reflections. The proposed scheme is parametric and can be tailored to a variety of research objectives, as it allows for adjustments in both the fraction of clusters and subpaths to be converted, as well as the specific multipath parameters to be modified. A theoretical analysis of the location error CRLB and numerical simulations of a simultaneous communication, localization, and mapping (SCLAM) algorithm both validate the model in a wide range of scenarios.