To solve problems related to Radio Frequency Identification, as well as to develop new technologies and applications with chipless RFID tags, this article describes the development of an innovative reader system based on Software-Defined Radios. Called SpuR, the system proposes a method of reading the spectral signature of RFID tags chipless, using general purpose hardware, reconfigurable by software, and operating in a wide frequency range without the need to change the reading equipment. This approach allows the accurate reading and identification of different types of chipless tags, using a classification procedure, by Euclidean distance, comparing them with a previously stored database.