{"title":"The analog voice privacy system","authors":"R. Cox, D. Bock, K. Bauer, J. Johnston, J. Snyder","doi":"10.1109/ICASSP.1986.1169066","DOIUrl":"https://doi.org/10.1109/ICASSP.1986.1169066","url":null,"abstract":"The Analog Voice Privacy System is based on individual sample permutation of the output samples of a sub-band coder analysis filterbank. The system has a large number of digital keys, giving it the strength of a digital encryption system, but also retains the good quality characteristics of analog scramblers. It has been implemented in a real-time hardware prototype designed for evaluation in the field. The units work with any modular telephone and standard 120 volts AC electricity. The device contains two circuitry boards, one for analog and one for digital processing which contain four digital signal processors. There are 125! possible permutation keys. These prototypes were designed to be tested in real telephone environments. To date, the device has been successfully tested over long distance telephone connections, several different analog and digital PBXs and telephone switches, and a channel simulator. The quality of the decrypted speech is considered very natural, and in particular, speaker recognition is retained. This is a significant advantage over digital vocoders. This paper describes the underlying principles of the algorithm, the details of its implementation and laboratory test results.","PeriodicalId":242072,"journal":{"name":"ICASSP '86. IEEE International Conference on Acoustics, Speech, and Signal Processing","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1987-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123927787","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A proposal of a knowledge based isolated word recognition","authors":"S. Morishima, H. Harashima, H. Miyakawa","doi":"10.1109/ICASSP.1986.1169202","DOIUrl":"https://doi.org/10.1109/ICASSP.1986.1169202","url":null,"abstract":"This paper describes a knowledge based isolated Japanese word recognition algorithm. The program is written with Prolog/KR [4] and has two basic inference processes, i.e., a Bottom-up search and a Top-down search. In the Bottom-up process, a segmentation and a vowel decision are performed and some target word patterns are generated. The Top-down process includes a consonant decision using a score of each candidate word calculated based on the Fuzzy Set Theory [1]. In the vowel inference, a template matching is applied mainly. In the segmentation, heuristic rules based on the spectrum transition and the wave form are used. But in the consonant inference, each rule has a hierarchy structure and it is defined automatically in the form of the multi-valued threshold function from learning data. This system can treat an obscure information about the consonant classification and to select the most effective decision rule in order to simplify the understanding process. The truth rate of consonant recognition is better than using statistical method.","PeriodicalId":242072,"journal":{"name":"ICASSP '86. IEEE International Conference on Acoustics, Speech, and Signal Processing","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1986-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117331061","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A network model dealing with focus of conversation for speech understanding system","authors":"Tetsunori Kobayashi, K. Shirai","doi":"10.1109/ICASSP.1986.1168665","DOIUrl":"https://doi.org/10.1109/ICASSP.1986.1168665","url":null,"abstract":"A new network model is proposed by introducing a special node called ε-node. This model makes flexible path weight control of the network representing the acceptable sentences (ASN) possible by giving a score to the ε-node. The path weight control strategy is developed using a rule based system, which has the ability to provide an adequate ASN according to the flow of conversation. Furthermore, a state transition network based system is adopted in order to follow and adapt to the changing topics of the conversation. Thus, a high speed and high reliable conversational speech understanding system is realized.","PeriodicalId":242072,"journal":{"name":"ICASSP '86. IEEE International Conference on Acoustics, Speech, and Signal Processing","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1986-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134320945","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Continuously variable duration hidden Markov models for speech analysis","authors":"S. Levinson","doi":"10.1109/ICASSP.1986.1168801","DOIUrl":"https://doi.org/10.1109/ICASSP.1986.1168801","url":null,"abstract":"During the past decade, the applicability of hidden Markov models (HMM) to various facets of speech analysis had been demonstrated in several different experiments. These investigations all rest on the assumption that speech is a quasi-stationary process whose stationary intervals can be identified with the occupancy of a single state of an appropriate HMM. In the traditional form of the HMM, the probability of duration of a state decreases exponentially with time. This behavior does not provide an adequate representation of the temporal structure of speech. The solution proposed here is to replace the probability distributions of duration with continuous probability density functions to form a continuously variable duration hidden Markov model (CVDHMM). The gamma distribution is ideally suited to specification of the durational density since it is one-sided and has only two parameters which, together, define both mean and variance. The main result is a derivation and proof of convergence of reestimation formulae for all the parameters of the CVDHMM. It is interesting to note that if the state durations are gamma distributed, one of the formulae is nonalgebraic but, fortuitously, has properties such that it is easily and rapidly solved numerically to any desired degree of accuracy. Other results are presented including the performance of the formulae on simulated data.","PeriodicalId":242072,"journal":{"name":"ICASSP '86. IEEE International Conference on Acoustics, Speech, and Signal Processing","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1986-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114950935","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Performance of narrowband signal-subspace processing","authors":"Hong Wang, M. Kaveh","doi":"10.1109/ICASSP.1986.1169009","DOIUrl":"https://doi.org/10.1109/ICASSP.1986.1169009","url":null,"abstract":"This paper presents an analytical evaluation of detection (determination of the number of sources) and estimation performances of narrowband signal-subspace processing for multiple-source direction finding. The probabilities of underestimating and overestimating the number of sources are derived, under asymptotic conditions and around threshold region, in terms of the choice of a penalty function and signal, noise and array parameters for the cases of at most two closely-spaced sources in the spatially white noise. A scalar measure is introduced for the evaluation of the quality of the estimated signal-subspace. Based on the statistics of this measure performance thresholds are demonstrated for the signal-to-noise ratio, angle separation and correlation between two equipowered sources.","PeriodicalId":242072,"journal":{"name":"ICASSP '86. IEEE International Conference on Acoustics, Speech, and Signal Processing","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1986-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127455492","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Spectrum enhancement using linear programming","authors":"R. Rothacker, R. Mammone, S. Davidovici","doi":"10.1109/ICASSP.1986.1168700","DOIUrl":"https://doi.org/10.1109/ICASSP.1986.1168700","url":null,"abstract":"In this paper a new approach to spectral analysis is presented. The method consists of two stages of processing. The first stage is used to reduce the variance of the noise. This stage of processing corresponds to many standard spectral estimation processes which involve averaging of one kind or another. This averaging stage is realized in this paper by using an adaptive line enhancer (ALE). The output of the ALE is a spectral estimate with reduced noise variance but a coarse frequency resolution. The second stage of processing is used to improve the frequency resolution of this coarse spectral estimate. The frequency resolution enhancement process is accomplished by a template matching method. The method uses Linear Programming to search for the best fit of(sin f)/ffunctions to the coarse spectral estimate. The position and scale factors of the(sin f)/ffunctions then yield the frequencies and amplitudes of the underlying sinusoids. The numerical results indicate that this second stage of processing gives a significantly better spectral estimate in terms of frequency accuracy (one tone) and resolution (two tone).","PeriodicalId":242072,"journal":{"name":"ICASSP '86. IEEE International Conference on Acoustics, Speech, and Signal Processing","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1986-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134057517","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Speech coder using phase equalization and vector quantization","authors":"T. Moriya, M. Honda","doi":"10.1109/ICASSP.1986.1169253","DOIUrl":"https://doi.org/10.1109/ICASSP.1986.1169253","url":null,"abstract":"A new speech processing and coding method is proposed which makes use of perceptual redundancy for slowly varying short-time phase characteristics. The method employs waveform conversion through a phase-equalizing filter, which is based on the time domain matched filter for the residue of Linear Predictive Coding (LPC). Phase-equalized speech is found to be almost perceptually equivalent and to be efficiently encoded by a two-stage quantization. In the first stage, vector quantization is performed for the pulse pattern in the time domain. In the second stage, vector-scalar quantization is applied to the spectral components using adaptive bit allocation. The proposed coder is proven to be superior to other coders both in terms of the SNR and the subjective quality. The averaged subjective quality at 9.6 kbps is comparable to that of a 6 bit log PCM.","PeriodicalId":242072,"journal":{"name":"ICASSP '86. IEEE International Conference on Acoustics, Speech, and Signal Processing","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1986-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125479328","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Range extended speech decoder for Modulo-PCM","authors":"M. Hagiwara, M. Nakagawa","doi":"10.1109/ICASSP.1986.1168987","DOIUrl":"https://doi.org/10.1109/ICASSP.1986.1168987","url":null,"abstract":"In this paper, we describe a new speech decoder for Modulo-PCM, which greatly reduces the \"anomaly errors\". Therefore, the proposed decoder can extend the dynamic range at the encoder input about 1.6-1.8 times compared to the conventional MPCM decoder.","PeriodicalId":242072,"journal":{"name":"ICASSP '86. IEEE International Conference on Acoustics, Speech, and Signal Processing","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1986-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130849135","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Hardware implementation of FM multipath distortion canceller","authors":"M. Itami, Takashi Mochizuki, M. Hatori","doi":"10.1109/ICASSP.1986.1168729","DOIUrl":"https://doi.org/10.1109/ICASSP.1986.1168729","url":null,"abstract":"The tap selecting digital adaptive FM multipath distortion canceller is described. In order to implement hardware of FM multipath distortion canceller, the convergence property of it is examined by computer simulation with finite bit length variables. As the result, a good DU ratio and fast convergence speed is confirmed. Moreover, simplification of hardware and structure of it is examined in practice.","PeriodicalId":242072,"journal":{"name":"ICASSP '86. IEEE International Conference on Acoustics, Speech, and Signal Processing","volume":"39 6","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1986-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120893393","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Spectral analysis of order statistic filters","authors":"A. Restrepo, A. Bovik","doi":"10.1109/ICASSP.1986.1168707","DOIUrl":"https://doi.org/10.1109/ICASSP.1986.1168707","url":null,"abstract":"We analyze the effect of filter coefficient selection on the power spectral density of an order statistic filtered signal. Assuming that the input signal is a sequence of independent and identically distributed random variates, the autocovariance and the power spectrum of the output are computed. These PSDs are compared with those of the corresponding linear finite impulse response filters with identical coefficients. It is found that, in general, low frequency components predominate regardless of coefficient selection, suggesting an inherent smoothing in the ordering process.","PeriodicalId":242072,"journal":{"name":"ICASSP '86. IEEE International Conference on Acoustics, Speech, and Signal Processing","volume":"89 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1986-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126463737","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}