1. A method of measuring proximity of an object to a sensor, the method comprising: supplying power to a first sensor, the first sensor comprising a ground plane, a first half wavelength strip filter, and a first patch, wherein the ground plane is separated from the first half wavelength strip filter by a first substrate, wherein the first half wavelength strip filter energizes the first patch, and wherein the first patch is separated from the half wavelength strip filter by a second substrate; and determining proximity of the object to the first sensor by measuring a signal component of the first sensor.