An example system drives one or more transmit signals on first electrodes disposed in a first layer and propagating electrodes disposed in a second layer. The system measures a capacitance of sensors through a of second electrodes. Each second electrode crosses each first electrode to provide a plurality of discrete sensor areas, each discrete sensor area associated with a difference crossing and including a portion of at least one propagating electrode. Each second electrode is galvanically isolated from the first electrodes and the propagating electrodes.