Patent Document ID: 10067575
Application ID: 13691637
Patent Status: 1

Claim One:
1. A stylus detection apparatus for detecting contacts from an active stylus, the apparatus comprising: a touch sensor panel comprising a plurality of electrodes configured to receive one or more signals generated by the active stylus, each respective electrode of the touch sensor panel is assigned, prior to receiving the one or more signals generated by the active stylus, a plurality of respective corresponding electrodes from which to generate a respective noise estimate for the respective electrode, wherein the plurality of respective corresponding electrodes are at fixed distances from the respective electrode and are separated from the respective electrode by at least one other electrode; and a processor including one or more analog front end circuits, the processor capable of: measuring a first signal from a first respective electrode coupled to a first input of the one or more analog front end circuits, the first signal including the one or more signals generated by the active stylus; measuring, simultaneously with measuring the first signal, a second signal from a first respective corresponding electrode of the plurality of respective corresponding electrodes assigned to the first respective electrode coupled to a second input of the one or more analog front end circuits and a third signal from a second respective corresponding electrode of the plurality of respective corresponding electrodes assigned to the first respective electrode coupled to a third input of the one or more analog front end circuits; generating a first respective noise estimate corresponding to the first respective electrode based on signals measured simultaneously with the first signal from the plurality of respective corresponding electrodes assigned to the first respective electrode, wherein the first respective noise estimate includes a weighted average of two or more of the simultaneously measured signals including the second and third signals; and adjusting the first signal measured from the first respective electrode by subtracting the first respective noise estimate.