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Objective estimation of perceived speech quality .II. Evaluation of the measuring normalizing block technique

S. Voran
1999 IEEE Transactions on Speech and Audio Processing  
When compared with six other estimators, significant improvements are seen in many cases, particularly at lower bit rates, and when bit errors or frame erasures are present.  ...  Together, these tests include 219 4-kHz bandwidth speech codecs, transmission systems, and reference conditions, with bit rates ranging from 2.4 to 64 kb/s.  ...  CELP B: 8 kb/s, over 9 RF channels, bit errors and frame erasures AMPS over 9 RF channels MNRU: 7 levels IRS filtered North American English 6 1050 100 3 27 ADPCM: 32 kb/s, clear and  ... 
doi:10.1109/89.771260 fatcat:lsjnny4glbdptbaoyzvcmoio4u

Combining Parametric And Waveform-Matching Coders For Low Bit-Rate Speech Coding

Jacek Stachurski, Alan Mccree
2000 Zenodo  
Publication in the conference proceedings of EUSIPCO, Tampere, Finland, 2000  ...  In independent evaluations, the coder achieved performance equivalent to ADPCM at 32 kb/s for clean speech and performed better than G.729 in the presence of 3% random frame erasures.  ...  In asynchronous tandeming, the 4 kb/s coder with two encodings was better than ADPCM at 32 kb/s with four encodings.  ... 
doi:10.5281/zenodo.37690 fatcat:2ioga4e6wvgktnnr7y5u5v4cqy

Speech transmission using rate-compatible trellis codes and embedded source coding

A. Bernard, Xueting Liu, R.D. Wesel, A. Alwan
2002 IEEE Transactions on Communications  
This paper introduces rate-compatible punctured trellis codes (RCPT) where rate compatibility and UEP are provided via progressive puncturing of symbols in a trellis.  ...  Performance results using an 8-PSK constellation clearly illustrate the wide range of channel conditions at which the adaptive scheme using RCPT can operate.  ...  With G.727, the source bitrate varies from 16 kb/s to 40 kb/s in steps of 8 kb/s.  ... 
doi:10.1109/26.983326 fatcat:hrlediouyfbznhyj3whjza7v2e

Wireless local loop radio systems

Nicolae Cotanis, Bijan Jabbari
1999 Computer Networks  
Characteristics of a wireless local loop system are partially different from those in the mobile cellular system and therefore their design and planning require different considerations.  ...  This paper provides first an overview of the wireless local loop systems and then discusses the important design aspects such as the necessary fade margin to achieve a given availability, level crossing  ...  kb/s ADPCM 32 kb/s ADPCM 32 kb/s ADPCM 32 kb/s ADPCM Time Slots per Frame 24 TS 24 TS 8 TS 8 TS Traffic CH per RF 12 12 3 7 Frame duration 10 ms 10 ms 5 2.5 ms Handset power (peak  ... 
doi:10.1016/s0169-7552(98)00271-2 fatcat:uyqsgydy2ngpbc4cnpraukxuv4

PACS: Personal Access Communications System-a tutorial

A.R. Noerpel, Yi-Bing Lin, H. Sherry
1996 IEEE personal communications  
Both modes of operation are supported using the same portable hardware and the same signaling protocol.  ...  The Personal Access Communications System (PACS) is an American National Standards Institute common air interface standard developed for the 1.9 GHz PCS band in the United States.  ...  Acknowledaments J The authors would like to thank all of the people who contributed to the development of the PACS wireless access system, especially Don Cox, Nelson Sollenberger, and Ken Felix.  ... 
doi:10.1109/98.511763 fatcat:fl56xcg5afhzbasfxfvpnhopa4

Innovative speech processing for mobile terminals: an annotated bibliography

André Gilloire, Pascal Scalart, Claude Lamblin, Chafic Mokbel, Stéphane Proust
2000 Signal Processing  
This paper gives an overview of recent bibliographic references dealing with speech processing in mobile terminals.  ...  Its purpose is to point out state of the art issues in the area; thus a fairly large list of references taken from many conferences proceedings and journals is given and commented.  ...  erential Pulse Code Modulation) G726 at 32 kb/s.  ... 
doi:10.1016/s0165-1684(00)00028-1 fatcat:oqswsxg24zgnvoomcgi6h3hjje

On the applications of multimedia processing to communications

R.V. Cox, B.G. Haskell, Y. LeCun, B. Shahraray, L. Rabiner
1998 Proceedings of the IEEE  
Today, the Internet (the largest of the existing packet networks) connects more than 40 million computers in some 140 countries.  ...  There are approximately 30 million users of the packet network in the United States, a number that is growing rapidly and will continue to do so over the next decade.  ...  ACKNOWLEDGMENT The authors wish to acknowledge that the original work described in this paper was done by a number of individuals at AT&T Laboratories as well as outside of AT&T.  ... 
doi:10.1109/5.664272 fatcat:yhn4kb3mmbctbbfus7br26oox4

Advances in objective estimation of perceived speech quality

S. Voran
1999 IEEE Workshop on Speech Coding Proceedings. Model, Coders, and Error Criteria (Cat. No.99EX351)  
We present two techniques that can be used to enhance objective estimators of perceived speech quality.  ...  Frame normalization and frame-energy plane partitioning are described and applied to a log-spectral-error-based estimator.  ...  Erasures) 13-16 11 Japanese IRS 27 ACELP, ADPCM, MNRU, (Bit Errors, Frame Erasures) 8-32 12 English IRS 27 Same as 11 8-32 13 French IRS 27 Same as 11 8-32 14 Italian IRS 27 Same  ... 
doi:10.1109/scft.1999.781510 fatcat:lpadbcssjfgojhdjvbyzdzxcbm

Algorithms and Software for Predictive and Perceptual Modeling of Speech

Venkatraman Atti
2011 Synthesis Lectures on Algorithms and Software in Engineering  
Moreover, provisions for quantizing the low-frequency subband at 32 or at 40 kb/s are available.  ...  Finally, error protection and frame erasure concealment techniques are also employed to improve the performance of the speech codec under channel errors [17] .  ...  which satisfy are retained, where T q (k) is the SPL of the threshold in quiet at spectral line k.  ... 
doi:10.2200/s00333ed1v01y201102ase007 fatcat:lo35wdmdijhypdt2omgfxdifxu

Speech and language processing for next-millennium communications services

R.V. Cox, C.A. Kamm, L.R. Rabiner, J. Schroeter, J.G. Wilpon
2000 Proceedings of the IEEE  
In the future, the world of telecommunications will be vastly different than it is today.  ...  and control problematic, and describes the types of voice services available in the past and today, and those that we foresee becoming available over the next several years.  ...  ADPCM coders have been created for bit rates ranging from 16 to 40 kb/s, with 32 and 40 kb/s giving good to excellent quality coded speech.  ... 
doi:10.1109/5.880086 fatcat:pzd6bawvirfo7c64t4zou2h4hy

Performance of voice over IP in mobile ad hoc networks

Hongqi Zhang, Université D'Ottawa / University Of Ottawa, Université D'Ottawa / University Of Ottawa
We implement the scheme in a test-bed and test the performance of speech in different scenarios using Multi-path Source Routing (MSR).  ...  The objectives of this thesis are to study the performance of voice over IP in ad-hoc networks, and to study the relationship among routing protocols, coding schemes and the quality of voice.  ...  For example, throughput of Scenario 1 reduces from 170 KB/s in static outdoor to 165 KB/s in static indoor, 160 KB/s in mobile outdoor, and eventually 150KB/s in mobile indoor.  ... 
doi:10.20381/ruor-12323 fatcat:zstgnmej7jfunlgcih6lws5efa

Internet Telephony over Wireless Links [article]

Christian Hoene, Technische Universität Berlin, Technische Universität Berlin, Adam Wolisz
We present and verify an instrumental approach on how to assess the perceptual quality of voice transmissions in IP-based communication networks.  ...  Wir entwickelten Verfahren, welche die Paketwichtigkeiten offline und in Echtzeit quantitativ bestimmen.  ...  Codec Coding rate [Kb/s] Speech quality [MOS] Applications G.723.1 5.3 or 6.8 3.8 Video telephony, VoIP G.729 8.0 4.0 Mobile telephony, VoIP G.711 64.0 4.5 Fixed telephone systems  ... 
doi:10.14279/depositonce-1329 fatcat:6aizw4ajhna4zbphcubj5njpqa