Patent ID: 7810716
Filing Date: 2010-10-12
Classification: B65H,G07D,G07F

Abstract:
1. An article bearing processor readable instructions operative to cause at least one processor to cause at least one apparatus to carry out a method comprising: a) directing a sound signal through a pathway through which sheet media moves; b) acquiring at least one receiver signal responsive to the sound signal, wherein at least a portion of the at least one receiver signal is produced responsive to the sound signal after having passed through the sheet media moving in the pathway; c) producing a first output representative of changes in phase of the at least one receiver signal relative to a first reference signal; d) producing a second output representative of changes in phase of the at least one receiver signal relative to a second reference signal, wherein the first and second reference signals differ in phase; e) acquiring a plurality of samples of the first and second outputs; f) comparing the samples of the first and second outputs to determine information corresponding to changes in phase of the sound signal after having passed through the sheet media; g) responsive to (f), moving the sheet media with at least one transport.