Channel state selection method and device based on ternary coding

Abstract

The invention discloses a channel state selection method and device based on ternary coding. The method includes the steps that a sound source signal is modulated into (2L+1) electric-level-grade quantitative signals x, mapping transformation is performed on the quantitative signals x so that control signals p, m and z can be generated, selection processing is performed on the control signals p, m and z and an M channel feedback signal b, then, an M channel state vector signal y is output, shape-correction processing is performed on the state vector signal y, then, the M channel feedback signal b is generated, and the state vector signal y completes electric-acoustic conversion through a multi-channel power amplifier and an energy converter. The device comprises a modulator module, a mapping module, a selection module, a shape-correction module, the multi-channel digital power amplifier and a loudspeaker array or a multi-voice-coil loudspeaker unit which are all connected in sequence. Through the method and device, hardware resource expenditure can be effectively reduced, hardware electric power consumption can be reduced, system stability is enhanced, the amplitude of an output signal can further be improved, conversion efficiency is improved, and meanwhile high signal-to-noise ratio output capacity is achieved.

Description

technical field [0001] The present invention relates to a digital loudspeaker encoding method and device, in particular to a channel state selection method and device based on three-state encoding. Background technique [0002] With the rapid development of VLSI manufacturing technology, the design and manufacture of loudspeaker systems, the leading product in the electro-acoustic industry, are gradually developing in the direction of low power consumption, miniaturization, and portability. In recent years, the semi-digital loudspeaker system driven by the wave of digitalization has successfully solved the power consumption and heat generation problems due to its use of Pulse Width Modulation (PWM) Class D power amplifier drive technology, and greatly improved the overall The electroacoustic conversion efficiency of the system. However, the rear stage of the semi-digital loudspeaker system still needs to rely on a bulky LC low-pass analog filter to filter out the out-of-ban...

AI Technical Summary

Problems solved by technology

The digital system based on 1-bit Δ-Σ modulation has the following defects while having the above-mentioned many advantages: ①It is sensitive to clock jitter, and it is easy to introduce nonlinear distortion due to clock jitter; ②In order to maintain the stability of the modulation structure The allowable dynamic range of the input signal is small; ③ requires a high switching rate, and the power MOSFET tube will generate more nonlinear distortion components in the process of driving the speaker load for high-speed switching, and will also cause MOSFET Increased tube heating, increased temperature and reduced efficiency

A three-state driving method is proposed in US patent US2014169577, but this patent does not explain how to select multi-channel three-state encoding, so it is impossible to avoid the influence of the deviation between multi-channels on the degradation of the system signal-to-noise ratio

[0007] The traditional three-state unit selection strategy is to divide the input signal into positive input and non-positive input, and then adopt the traditional two-state unit-based dynamic mismatch shaping selection strategy for the two types of input. This strategy can be inherited from the original Minor changes are made on the basis of the design, and the structure is simple, but the signal-to-noise ratio of the output signal after shaping is low, and it changes with frequency changes

Although this traditional three-state selection strategy reduces the resource occupation of hardware implementation, it also sacrifices the output signal-to-noise ratio performance

US Patent US20120057727 proposes a strategy of using channel average and time average to select tri-state units, but this strategy has two defects: (1) This method only gives the selection when the input signal is close to 0 The strategy does not give the selection strategy under other input conditions; (2) The time averaging strategy method will destroy the original signal and easily introduce harmonic distortion

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