Patent ID: 9013277
Filing Date: 2015-04-21
Classification: G06K

Abstract:
1. A method of allocating digital data coming from transponders, comprising the steps of: receiving at a reader a first signal that comprises a first signal component coming from a first transponder and a second signal component coming from a second transponder during a same time slot in which the first and second transponders respond to an inventory command from the reader at different time points, wherein digital data coming from the first transponder are encoded in the first signal component and digital data coming from the second transponder are encoded in the second signal component; generating second and third signals by subjecting the first signal to an in-phase and to an in-quadrature demodulation; and allocating clusters of the digital data associated with a constellation diagram, which is related to the second and third signals, to the first and second transponders, wherein a first pair of the clusters is only related to the first transponder, a second pair of the clusters is only related to the second transponder, the centers of gravity of the first pair of the clusters are symmetric to the origin of the constellation diagram, and the centers of gravity of the second pair of the clusters are symmetric to the origin of the constellation diagram.