Patent ID: 6382516
Filing Date: 2002-05-07
Classification: G06K

Abstract:
A security system comprising:a portable secure object; and a terminal for use with said portable secure object, said portable secure object including: means for storing information, and means for storing a coded sound signal or a signal indicative thereof, microphone means, means responsive to said microphone means for generating said coded sound signal during a registration procedure, wherein said microphone means is formed integrally with said portable secure object, wherein during use an output derived from said microphone means is subsequently used for deriving in said terminal a further coded sound signal for comparison with said generated coded signal for subsequent coded sound interrogation purposes, wherein said terminal comprises: sound transmission means for transmitting a sound signal input to said terminal to the microphone means of said portable secure object, signal processing means responsive to an electrical signal from said microphone means for generating a coded signal indicative of said sound signal, and means for applying a signal to said portable secure object corresponding to said coded signal, and wherein said signal processing means comprises a plurality N of signal comparators, each signal comparator being adapted to compare the electrical signal from said microphone means with a plurality of different exemplar signals and for affording an output indicative of which of said exemplar signals corresponds most closely to said electrical signal, the sets of exemplar signals of each of said signal comparators being different, said electrical signal being input to each of said signal comparators to derive an N-part coded signal which is indicative of said sound signal.