A cascaded oscillator array includes a first oscillator array and a second oscillator array. The first oscillator array includes at least three oscillator elements coupled unidirectionally in a first ring such that the first oscillator array outputs a first oscillating signal. Each of the at least three oscillator elements is coupled to receive a signal from a sensing element. The second oscillator array includes at least three oscillator elements coupled unidirectionally in a second ring such that the second oscillator array outputs a second oscillating signal. A first number of the at least three oscillator elements of the first oscillator array is the same as a second number of the at least three oscillator elements of the second oscillator. Each oscillator element of the at least three oscillator elements of the second oscillator array is coupled to receive an output signal from a single oscillator element of the at least three oscillator elements of the first oscillator.