DEVICE FOR INPUTTING NATURAL NOTE INFORMATION USING ADAPTATION ALGORITHM

摘要

PURPOSE: A device for inputting the natural note information using an adaptation algorithm is provided to keep a digital conversion signal at a constant phase by controlling a critical value according to a distance separated from a center of a received signal. CONSTITUTION: An ultrasonic sensor(101) receives an ultrasonic signal. An infrared receiver(200) receives an infrared signal. A signal processor(102) converts the ultrasonic signal into above a constant size by filtering and amplifying the ultrasonic signal among the received signals. A digital converter(103) includes a comparator for converting the signal outputted from the signal processor into a digital signal. A counter(104) counts a time between a standard synchronization signal received by the infrared receiver and the digital signal. A distance generating tool(105) calculates the distance of a transmitter based on the timing information. An adaptation coefficient generating tool generates a coefficient related to a critical voltage or the amplification. A coordinates calculator(300) calculates the absolute coordinates from the calculated distance information.