Material e.g. non-metal, identifying method for e.g. football stadium, involves determining type of object on basis of agreement between characteristics and database stored in other characteristic

摘要

The method involves providing a database of transmission character statistics and/or reflection characteristics of materials e.g. non-metal, while sending ultrasonic sound wave (23) to a test object (X). An induced ultrasonic signal (24) is provided to a receiver-transducer (4) while receiving the object. The characteristics of the object are calculated on the basis of the received signal. The characteristics are compared with data in the database. A type of the object is determined on the basis of an agreement between the characteristics and a database stored in other characteristic.