A capacitive sensing device has a first plurality of sensor electrodes, and a second plurality of sensor electrodes overlapping the first plurality of sensor electrodes. A first sensor electrode of the second plurality of electrodes overlaps a first subset of the first plurality of electrodes and comprises apertures disposed according to first codes. The first codes comprise first and second coefficients and along one of the first plurality of sensor electrodes. Each aperture may correspond to one of the first coefficients. The capacitive sensing device further comprises a processing system coupled to the first and second plurality of sensor electrodes. The processing system may be configured to receive resulting signals with the second plurality of sensor electrodes to determine positional information for an input object within a sensing region of the capacitive sensing device.