Patent ID: 8378974

Claim:
A method of detecting a touch event on a touch panel, comprising: obtaining a first signal from at least a first sensor and a second signal respectively from at least a second sensor, where the first and second signals are responsive to a touch event; digitizing the first signal to form a first set of digitized signals and the second signal to form a second set of digitized signals; performing a frequency transform upon the first and second sets of digitized signals to form respectively first and second frequency transform data sets of frequency components; calculating a first amplitude magnitude associated with the first signal and calculating a second amplitude magnitude associated with the second signal, the first amplitude magnitude being calculated based on the first frequency transform data set and the second amplitude magnitude being calculated based on the second frequency transform data set; determining a magnitude ratio between the first amplitude magnitude associated with the first frequency transform data set and the second amplitude magnitude associated with the second frequency data set; and identifying a location of the touch event based on the magnitude ratio, the magnitude ratio being gauge-invariant.