US Patent 10969908 Using multiple signals to detect touch input

Detecting a location of a touch input is disclosed. Each of a plurality of transmitters coupled to a propagating medium emits a signal that is distinguishable from other signals emitted from other transmitters. The signals from the transmitters are received from at least one receiver coupled to the propagating medium to detect the location of the touch input on a surface of the propagating medium as indicated by an effect of the touch input on each of the distinguishable signals.