Ranging method based on summation of multi-frequency audible sound wave amplitude

Abstract

The invention discloses a multifrequency hearable sound wave amplitude summation-based distance measurement method, mainly for solving the problems of high synchronization requirement and big accidental error of present single frequency hearable sound wave distance measurement. The distance measurement method comprises the following implementation steps: (1) arranging a hearable sound wave generator, and emitting multifrequency hearable sound waves; (2) collecting sound wave signals for multiple times at different distances, performing FFT transformation, acquiring a sum of multifrequency sound wave amplitudes at the different distances, and using matlab to obtain a sound wave channel module; (3) collecting a sound wave signal by a sound wave collection device, and performing FFT transformation to obtain a sum of multifrequency amplitudes; (4) obtaining a distance measurement value according to the sum of multifrequency amplitudes and the sound wave channel module; (5) repeating the steps (3) and (4) to obtain multiple distance measurement values, removing abnormal distance measurement values, and averaging the rest values to obtain a final distance measurement value. The method reduces the accidental error of distance measurement, improves the distance measurement stability, and can be used for short distance measurement between devices.

Description

technical field [0001] The invention belongs to the technical field of wireless communication, and further relates to the field of sound wave ranging, which can be used for short-distance ranging between devices. Background technique [0002] At present, the non-contact distance measurement system has been applied in various fields of real life. Compared with the traditional contact distance measurement, it has higher accuracy, more convenient operation and higher safety factor. [0003] The existing ranging methods with more applications include microwave radar ranging, laser ranging, ultrasonic ranging and so on. For some devices, such as mobile phones, computers, etc., the above three ranging methods need to add additional hardware, thereby increasing hardware complexity and cost. Using the built-in speakers and microphones of these devices to transmit and receive audible sound waves can complete short-distance ranging. The existing methods of using audible sound wave r...

AI Technical Summary

Problems solved by technology

The time difference-based ranging method measures the distance by accurately measuring the time difference between the sound wave emitted by the transmitter and the sound wave received by the receiver. In order to achieve this goal, time synchronization must be performed between the transmitter and the receiver. It is very difficult to achieve accurate time synchronization between the transmitting end and the receiving end. The speed of sound propagation is 340m / s, and the distance between the transmitting end and the receiving end is generally within 10m, that is, the sound from a node It only takes about 0.03s to transmit to its adjacent nodes. Considering noise interference, measurement error and processing delay, it is very difficult to distinguish such a small time difference

Since the sound wave propagation process is relatively regular, the collected signal is relatively stable and reliable. Compared with other physical measurement properties, sound energy can be sampled at a lower rate, and does not require time synchronization between the transmitter and receiver. However, the use of single-frequency sound waves for ranging will cause large accidental errors, which will affect the accuracy of ranging

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