A testing device and method for audio-frequency directional system performance

Abstract

The invention relates to a testing device and method, specifically a testing device and method for the performances of an audio frequency directional system. The testing device comprises a transmitting end and a receiving end. The transmitting end comprises an audio signal generator, a carrier generation circuit, a first signal processing circuit, a power amplification circuit, an ultrasonic transducer, and a first oscilloscope. The receiving end also comprises a sound pickup, a second signal processing circuit, and a second oscilloscope. The testing method comprises the following steps: (1), connecting the first and second oscilloscopes; (2), adjusting the first and second oscilloscopes; (3), adjusting a testing distance; (4), carrying out data testing; (5), arranging test data. The device is simple in circuit design, is convenient to install, and can accurately measure the basic performance parameters of frequency response and harmonic distortion of the audio frequency directional system. Moreover, the test data is true and reliable. In addition, the device and method are higher in universality and expansibility, can be used for the testing of different types of audio frequency directional systems, and also can be used for the verification of the performance and feasibility of a signal preprocessing method of the audio frequency directional system.

Description

technical field [0001] The present invention relates to a testing device and its method, more specifically, to a testing device and its method for the performance of an audio-frequency directional system. Background technique [0002] In daily life, the sound propagation of most speakers is divergent, and the sound waves will propagate outward in the form of spherical waves, so the sound does not have obvious directivity. When multiple sound sources exist at the same time, mutual interference will inevitably occur. Case. With the continuous progress of society, people's needs are also increasing, and many occasions require a directional sound source. For example, in museums, supermarkets, exhibitions and other occasions, the audio introductions of different commodities or exhibits will be mixed together, causing the scene to be noisy and chaotic. If a directional sound source can be used so that only the audio introductions can be heard near the commodities or exhibits, it ...

AI Technical Summary

Problems solved by technology

[0004] At this stage in China, there are relatively in-depth researches on the research of signal preprocessing algorithms, but there are certain problems in system testing. As a result, in the existing domestic literature, there is no method that can accurately test reliable experimental data, which is different from theirs. Circuit design and test methods have a certain relationship

In terms of circuit design, most of the final power amplifiers used in the existing literature are Class-D power amplifiers and a design scheme that adds a load matching circuit. Although this method has high efficiency, its signal fidelity and frequency response curve are not enough. Ideal, it is easy to cause serious harmonic distortion and frequency response fluctuations; in terms of system test methods, in the existing literature, only the low-frequency audible signals obtained by nonlinear demodulation are tested during the test process, and the original sound waves are completely ignored. That is, the ultrasonic part, once the amplitude of the ultrasonic component in the received signal exceeds the upper limit of the amplitude response of the pickup, additional harmonic distortion will be introduced

Due to the above reasons, there is no completely true and reliable data in the actual system test data of the existing domestic literature, so a device and method that can accurately test the performance of the audio directional system are needed

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