Channel state selection method and device based on tri-state encoding

Abstract

Disclosed are a channel state selection method and device based on ternary coding. The method comprises: performing modulation processing on a sound source signal to generate (2L+1) level quantization signals x; performing mapping transformation on the quantization signals x to generate control signals p, m and z; performing selection processing on the control signals p, m and z and an M-channel feedback signal b, and then, outputting an M-channel state vector signal y; performing shaping processing on the state vector signal y, and then, generating the M-channel feedback signal b; and completing electric-acoustic conversion after the state vector signal y passes through a multi-channel power amplifier and an energy converter unit. The device comprises a modulator module, a mapping module, a selection module, a shaping module, and a multi-channel digital power amplifier and a loudspeaker array or a multi-voice-coil loudspeaker unit module, which are connected in sequence. The present invention can effectively reduce hardware resource overheads, reduce hardware power consumption, improve system stability, further improve the amplitude of an output signal, and improve conversion efficiency, and has a high signal-to-noise ratio output capacity.

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 problems of power consumption and heat generation because of 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...

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, higher temperature and lower efficiency

US2014169577 proposes a three-state driving method, 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 multiple 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 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 strategy, and 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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