排序方式: 共有112条查询结果,搜索用时 15 毫秒
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介绍了一种基于VQ的小词汇量特定人快速语音识别方法,并对该方法中的关键参数进行了比较性研究. 这一方法尤其适用于汉语特定人小词汇量语音识别. 与典型的HMM和NN识别算法相比,该方法复杂度低、系统资源消耗少而识别率高,在对汉语11个数字的大规模识别测试中误识率仅为3.86%. 因此,该方法适合于在手机、PDA等资源有限的系统中实现语音数字拨号、人名拨号及查询等语音控制功能. 相似文献
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Associated with ITU-T G.719,a post-processing method in frequency domain for enhancing the perceptual quality of the decoded transient audio is proposed only to the audio decoder with no side information from the encoder.The proposed post-filter is used to filter the frequency coefficients of the decoded transient frame and consists of a short-term post-filter and a spectral tilt compensation filter which are derived from linear predictive coding(LPC) predictor based on the discrete cosine transform(DCT) coefficients of the decoded transient frame.As a result,the post-filter in frequency domain shapes the temporal noise in time domain and controls the pre-echo noise effectively while enhancing the transient perception.Listening test results show that the preferring ratio of the post-processed transient signal is higher than that of the original decoded signal at a low bit rate of 32 kbit/s in G.719 and the post-processing module brings a complexity of 12.399 WMOPS to the decoder. 相似文献
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A new Chien search method for shortened Reed-Solomon(RS) code is proposed,based on this,a versatile RS decoder for correcting both errors and erasures is designed.Compared with the traditional RS decoder,the weighted coefficient of the Chien search method is calculated sequentially through the three pipelined stages of the decoder.And therefore,the computation of the errata locator polynomial and errata evaluator polynomial needs to be modified.The versatile RS decoder with minimum distance 21 has been synthesized in the Xilinx Virtex-Ⅱ series field programmable gate array(FPGA) xc2v1000-5 and is used by concatenated coding system for satellite communication.Results show that the maximum data processing rate can be up to 1.3 Gbit/s. 相似文献
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An extended phonemic set of mandarin from the view of speech recognition is proposed. This set absorbs most principles of some other existing phonemic sets for mandarin, like Worldbet and SAMPA-C, and also takes advantage of some practical experiences from speech recognition research for increasing the discriminability between word models. And the experiments in speaker independent continuous speech recognition show that hidden Markov models defined by this phonemic set have a better performance than those based on initial/final units of mandarin and have a very compact size. 相似文献
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An adaptive modulation and coding (AMC) scheme integrated with multi-code transmission for high speed downlink packet access is presented and some modulation and coding scheme (MCS) selection criteria are proposed to maximize single user data rates. Based on link-level performance analysis, the MCS selection criteria are proposed with the constraints of QoS requirement, modulation level, channel coding rate and the number of available channelization codes. By allowing multiple transmission parameters changing, these criteria make the scheme more flexible to time-varying mobile channel with comparatively low complexity through a look-up table method. The AMC scheme is sensitive to the changes of channel condition and can save the channelization codes in an applicable way by applying these criteria. 相似文献
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Reliability Evaluation of Mobile Communication Networks 总被引:1,自引:0,他引:1
A new reliability evaluation measure, global clustering reliability (GCR), is proposed. Firstly, the common measures used in invulnerability and survivability evaluation of mobile communication networks are discussed, and the shortcomings of these measures are pointed out. Then a new reliability evaluation measure, GCR, which is applicable to mobile communication networks, is proposed. And some properties and theorem about this measure are put forward. Finally, simulation calculation of reliability evaluation that uses this measure to 12 kinds of topological networks is accomplished. And the comparison between this measure and link connected factor (LCF) measure is also given. The results proved that the design of GCR is reasonable, its computation is rapid, moreover, it can take into account of invalidation of both nodes and links, and it has good physical meanings 相似文献
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A Bark-band residual noise model integrated with the human hearing mechanism is proposed to efficiently complement sinusoidal model in parametric audio coding. The time-varying spectrum of the residual noise is retrieved by Bark-scale piecewise constant magnitude estimates along with random phases. In the proposed noise model, Bark bands information is obtained by short-time FFT method and window overlap-add technique is exploited to remove boundary discontinuities. SVQ is also incorporated into parameter quantization process for the low bit-rate coding demand. Simulation results and informal listening tests show that when the sinusoidal model is combined with the Bark-band noise model, better synthesis audio quality can be achieved compared with the original sinusoidal modeling audio codec. 相似文献
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