Abstract: The invention provides a two-phase flow active and passive multi-level data center cabinet cooling device and method, wherein the system includes a cabinet cooling device, a condensate system, a waste heat recovery device, a liquid reservoir, a liquid pump, a gas chamber, a fluid working medium, and a corresponding pipeline. The system comprise a closed loop, the loop is filled with nitrogen to maintain a low pressure state, and the pipeline fluid is driven by the liquid pump to flow; the gas chamber maintains a relatively stable air pressure in the two-phase flow loop; the liquid reservoir is connected with the gas chamber, providing an enough gas space to make a phase change occur more easily; the cabinet cooling device can be switched between an active mode and a passive mode to minimize PUE under good heat dissipation capability.

Abstract: Embodiments of this application relate to the field of terminal technologies, and provides a millimeter wave module circuit and a terminal device. The first antenna array includes N first antennas, and the second antenna array includes M second antennas, where N is greater than M. The processing module includes a plurality of first processing units. Each of N first antennas is connected to each first processing unit. Each of M second antennas is separately connected to two different first processing units. The first processing unit includes a power amplifier. The processing module is configured to send, through differential feeding, a second signal to the second antenna by using two different first processing units. This can enable a signal coverage of the second antenna array to be increased, improving performance of a millimeter wave module in a coverage region of the second antenna array.

Abstract: The present document relates to a voice activity detection (VAD) method and methods used for voice activity detection and apparatus thereof, the VAD method includes: obtaining sub-band signals and spectrum amplitudes of a current frame; computing values of a energy feature and a spectral centroid feature of the current frame according to the sub-band signals; computing a signal to noise ratio parameter of the current frame according to a background noise energy estimated from a previous frame, an energy of SNR sub-bands and a energy feature of the current frame; computing a VAD decision result according to a tonality signal flag, a signal to noise ratio parameter, a spectral centroid feature, and a frame energy feature. The methods and apparatus of the present document can improve the accuracy of non-stationary noise (such as office noise) and music detection.

Abstract: The present document relates to a voice activity detection (VAD) method and methods used for voice activity detection and apparatus thereof, the VAD method includes: obtaining sub-band signals and spectrum amplitudes of a current frame; computing values of a energy feature and a spectral centroid feature of the current frame according to the sub-band signals; computing a signal to noise ratio parameter of the current frame according to a background noise energy estimated from a previous frame, an energy of SNR sub-bands and a energy feature of the current frame; computing a VAD decision result according to a tonality signal flag, a signal to noise ratio parameter, a spectral centroid feature, and a frame energy feature. The methods and apparatus of the present document can improve the accuracy of non-stationary noise (such as office noise) and music detection.

Abstract: A parameter estimation method for inactive voice signals and a system thereof and comfort noise generation method and system are disclosed. The method includes: for an inactive voice signal frame, performing time-frequency transform on a sequence of time domain signals containing the inactive voice signal frame to obtain a frequency spectrum sequence, calculating frequency spectrum coefficients according to the frequency spectrum sequence, performing smooth processing on the frequency spectrum coefficients, obtaining a smoothly processed frequency spectrum sequence according to the smoothly processed frequency spectrum coefficients, performing inverse time-frequency transform on the smoothly processed frequency spectrum sequence to obtain a reconstructed time domain signal, and estimating an inactive voice signal parameter according to the reconstructed time domain signal to obtain a frequency spectrum parameter and an energy parameter.

Abstract: A parameter estimation method for inactive voice signals and a system thereof and comfort noise generation method and system are disclosed. The method includes: for an inactive voice signal frame, performing time-frequency transform on a sequence of time domain signals containing the inactive voice signal frame to obtain a frequency spectrum sequence, calculating frequency spectrum coefficients according to the frequency spectrum sequence, performing smooth processing on the frequency spectrum coefficients, obtaining a smoothly processed frequency spectrum sequence according to the smoothly processed frequency spectrum coefficients, performing inverse time-frequency transform on the smoothly processed frequency spectrum sequence to obtain a reconstructed time domain signal, and estimating an inactive voice signal parameter according to the reconstructed time domain signal to obtain a frequency spectrum parameter and an energy parameter.

Abstract: Hierarchical audio coding and decoding method and system and hierarchical audio coding and decoding method for transient signals are provided. In the present invention, by introducing a processing method for transient signal frames in the hierarchical audio coding and decoding methods, a segmented time-frequency transform is performed on the transient signal frames, and then the frequency-domain coefficients obtained by transformation are rearranged respectively within the core layer and within the extended layer, so as to perform the same subsequent coding processes, such as bit allocation, frequency-domain coefficient coding, etc., as those on the steady-state signal frames, thus enhancing the coding efficiency of the transient signal frames and improving the quality of the hierarchical audio coding and decoding.

Abstract: The present invention relates to a method and system for audio encoding and decoding and a method for estimating a noise level, and the method for estimating a noise level in the present invention comprises: estimating a power spectrum of an audio signal to be encoded according to a frequency domain coefficient of the audio signal to be encoded; and estimating a noise level of a zero bit encoding subband audio signal according to the power spectrum obtained by calculating, and this noise level for controlling an energy proportion of noise filling to spectral band replication during decoding; wherein a zero bit encoding subband refers to an encoding subband of which allocated bit number is zero. The present invention can well reconstruct the uncoded frequency domain coefficients.

Abstract: The present invention relates to a method and system for audio encoding and decoding and a method for estimating a noise level, and the method for estimating a noise level in the present invention comprises: estimating a power spectrum of an audio signal to be encoded according to a frequency domain coefficient of the audio signal to be encoded; and estimating a noise level of a zero bit encoding subband audio signal according to the power spectrum obtained by calculating, and this noise level for controlling an energy proportion of noise filling to spectral band replication during decoding; wherein a zero bit encoding subband refers to an encoding subband of which allocated bit number is zero. The present invention can well reconstruct the uncoded frequency domain coefficients.

Abstract: The present invention relates to a method and device for spectral band replication, and a method and system for audio decoding, and the method for spectral band replication comprises: A. searching for the position of a certain tone of an audio signal in MDCT frequency domain coefficients; B. according to the tone position, determining a spectral band replication period which is a bandwidth from a 0 frequency point to a frequency point of tone position, and a source frequency segment which is a frequency segment from a frequency point of the 0 frequency point shifting copyband_offset frequency points backwards to a frequency point of the frequency point of the tone position shifting the copyband_offset frequency points backwards, wherein said offset copyband_offset is greater than or equal to 0; and C. according to the spectral band replication period, carrying out spectral band replication on zero bit encoding subbands.

Abstract: Hierarchical audio coding and decoding method and system and hierarchical audio coding and decoding method for transient signals are provided. In the present invention, by introducing a processing method for transient signal frames in the hierarchical audio coding and decoding methods, a segmented time-frequency transform is performed on the transient signal frames, and then the frequency-domain coefficients obtained by transformation are rearranged respectively within the core layer and within the extended layer, so as to perform the same subsequent coding processes, such as bit allocation, frequency-domain coefficient coding, etc., as those on the steady-state signal frames, thus enhancing the coding efficiency of the transient signal frames and improving the quality of the hierarchical audio coding and decoding.