Optical accessing by using speckle patterns generated by the chirp Z transform

FABIAN MOSSO; MYRIAN TEBALDI; ROBERTO TORROBA; NESTOR BOLOGNINI

Lima

Congreso; VII Reunión Iberoamericana de Óptica (VII RIAO) y X Encuentro Latinoamericano de Óptica, Láseres y sus Aplicaciones (X OPTILAS); 2010

Pontificia Universidad Católica del Perú

We present an accessing scheme to confidential information by using the chirp Z transform (CZT) applied to a master speckle pattern. The keymaster, which authorizes acceding to the information, has at his disposal a database of each user. Every user has assigned three verification points ruled by spatial coordinate positions and frequency resolution on the input image, much like as in the procedure followed in ATMs. That is, the user possess a reconfigurable random key where the verification points are obtained based on coordinates and resolution frequency parameters obtained from the CZT applied to the master speckle pattern. Then, if the three verification points are confirmed by means of an optical correlation operation, the user accedes to the confidential information. We show several examples to verify the proposal.