Systems and methods to generate maps or models of structures are disclosed. Features of the structure to be mapped may be determined for the purposes of generating the map or model based at least in part on images associated with the structure, sensor measurements associated with the structure, and phase data of communications signals that interact with the structure. The mapping or modeling processes may be performed at a mapping server that receives images, sensor data, and/or communications signal phase information from one or more user devices, such as mobile devices. The mapping servers may perform a simultaneous localization and mapping (SLAM) process and may enhance the generated maps using sensor and/or communications phase data to map one or more hidden features of the structure.