This paper presents an extension of the SCHUN (Simplified CHannel for Urban Navigation, [1]) simulator and its validation framework in a wideband context. The hybrid physical-statistical model on which this simulator relies on extends the scope of applicability of standard channel characterization models thanks to its physical modeling of the interactions between the environment and a receiver. It also allows the generation of frequency and polarization diversities, and it improves the representativeness of the urban environment (type of materials, roughness...) while keeping a reasonable computational payload. This model has been validated in a narrowband and wideband context with respect to data acquired in a LMS (Land Mobile Satellite) configuration.