Adaptive Ultrasonic Distance Measurement Technique for Handwriting Digitization Using Reconfigurable Analog Blocks

This paper proposes a low-power dynamically adaptive distance measurement technique for ultrasonic (US) pen digitizers. The technique utilizes a new clock frequency-throttling technique for a reconfigurable analog front-end in implementing a frequency-hopping scheme to minimize power dissipation. As a result, a noise-tolerant distance measurement which is not possible in conventional schemes is realized. Furthermore, the use of reconfigurable analog blocks facilitates wider bandwidth usage of the Piezo film transducers that are used for ultrasonic transmissions and receptions.