On the performance of a backscattering based tomographic imaging technique in reduced angular extent exploration

In non-invasive. non-destructive testing of marerial a common problem is the detect'ion and location of small unwan{ed ir.clusions inside the material bulk caused by faults in the manufacturing process. The methods used for this pur-pose ar-e generally based on the inreraction between an acoustic or electromagnetic wave with the material being tested and are commonly derived from radar or sonar techniques. With such methods, the resolution performance is strictly dependent on the geometrical size of the volume of material interacting with the exploring wave. Therefore an imprcvement in resolution requ ires an improvement in the focalization propenies of the radiating system, and a consequent increase in design and construction difficulties.