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I would like the proposers to take a pass through the citation and define or reevaluate the use of acronyms. The plaque should be accessible to members of the public who may not know what all terms mean.
Thank you very much for your comments. I agree with your opinion and tried to avoid acronyms. I am now proposing the following citation: --- Line Spectrum Pair, invented at NTT in 1975, is an important technology for speech synthesis and coding. A speech synthesizer chip was designed based on Line Spectrum Pair in 1980. In the 1990's, this technology was adopted in almost all international speech coding standards as an essential component and has contributed to the realization of digital speech communication over mobile channels and the internet worldwide. ---
Every telephone company / manufacturer has their own way of doing things: chips, algorithms, techniques and methods for compressing, transmitting, and receiving speech. Not every design that comes out of a company's laboratory rises to the level of IEEE Milestone. NTT 's particular brand of compressing speech is based on a subset of Line Prediction Coding - LPC. Is LSP a real technology or just another math procedure? Is the LSP licensed to other radio manufacturers?
NTT's LSP design was simply accommodated by international standards. NTT did not invent nor create these standards but certainly have encouraged their formation, together with others, and deliberated to ensure their products would be accommodated over mobile channels and the internet. Getting their standards recognized by world bodies was a business or regulatory decision and is not especially noteworthy. Everybody does it.
The phrase ...' contributed to the realization of digital speech communication over mobile channels and the ....". is a bit overstated by suggesting that NTT contributed to my ability to communicate. People in Boston have always found a way to communicate wherever we wanted ever since the days of Alexander G Bell.
Thank you for your comments. I would like to add some explanations on LSP and the standardization process. LSP is the name of a signal processing technology invented at NTT; it is not a brand name. For the Japanese cellular phone system (PDC: Public Digital Cellular) standardized in 1993, LSP, as well as other essential technologies invented at NTT, has been licensed to all organizations (service providers, chip and system manufacturers) for free. For all other internal standardizations on speech and audio coding, NTT has licensed the essential technologies to all with reasonable and nondiscriminatory conditions. For speech and audio compression technologies, standardization of specifications is essential to ensure interoperability among many users and operators. For most of the international standards of speech and audio coding methods for cellular and IP phones created at ITU-T, 3GPP, and 3GPP2, the specifications were decided by a process of serious technical competitions or technical evaluations based on subjective listening tests. On the basis of the results, it was found that the selected scheme, either proposed by NTT or by other organizations, should use LSP technology as a representation tool of spectrum, because performance was degraded without it. The technical merits of LSP have been proven by numerous speech coding experts throughout the world.
I may admit that “contributed to the realization of digital speech communication over mobile channels and the..” may be replaced with “contributed to the enhancement of digital speech communications over mobile channels and the..” We appreciate your comments and advice.
I contacted Bishnu Atal, formerly at Bell Labs, and a pioneer in the field. He supports this nomination. I too feel the technology and its invention by NTT investigators are worthy of milestone status.
I received an opposite comment from Dr. Clifford J. Weinstein, of the Human Language Technology, MIT Lincoln Laboratory: "I agree that Line Spectrum Pair Technology for Speech Coding does not qualify as an IEEE milestone. The whole topic of LPC may qualify. However it has many inventors at a number of locations."
We agree that LPC (Liner Predictive Coding), as a fundamental , has had a great impact on the of speech-related technologies, including , enhancement, coding, recognition and synthesis. LPC is based on a framework of and was first applied to speech signal by Dr. B. S. Atal and Dr. F. Itakura independently . Lots of practical variations and extensions of LPC have been invented and some of them have been applied to proprietary commercial products in individual markets. LSP is one of the inventions based on LPC, but it is special because it has been commonly adopted in digital communications systems ( and phones) and has been used by billions of users around the world. Experts think LSP will be continuously used well into the future. LSP was born and brought up by many researches in the community. It is worthwhile that great contributions from the community are widely recognized by all users.
 B. S. Atal, “The History of Linear Prediction”, , pp. 154-157, MARCH 2006.