1. An active radiation source portal monitoring system comprising: a particle accelerator as a source of charged particles; a charged particles control unit to control the charged particles to enter into a volume to be scanned in a desired direction to interact with an object located in the volume; a particle tracking unit arranged at a location near the volume to detect the charged particles exiting the volume after interacting with the object and generate signals indicative of information on the charged particles exiting the volume; and a signal processing unit communicatively coupled to the particle tracking unit, the signal processing unit to receive the generated signals and to analyze scattering of the charged particles in one or more materials included in the object based on the received signals indicative of the information on the charged particles exiting the volume to obtain a tomographic profile or a spatial distribution of scattering centers within the object.