A few years ago, the company put in a high-bandwidth telephone line, known as an I.S.D.N., and will move to an even faster line, a T1, this month.
In particular, the acoustic models used in automatic speech recognition (ASR) or speaker diarization can be trained for specific acoustic conditions, such as clean studio versus noisy outdoor speech, or high-quality wide-bandwidth studio versus low-quality narrow-bandwidth telephone speech.
Five studies, all of which were home care, used the PSTN Public Switched Telephone Networkk), which is the standard low-bandwidth telephone line supplied to households, and three studies did not specify the connectivity.
The higher formants of children fall outside the transmission bandwidth of telephone channel resulting in the loss of the spectral information in case of narrowband speech recognition.
A system for bandwidth extension of telephone speech, aided by data embedding, is presented.
This mapping technique is also used for bandwidth extension of telephone speech.
Very high-speed digital subscriber line (VDSL) systems optimize the use of available bandwidth of the telephone lines for broadband transmissions [1].
While existing telephone bandwidth was ample for voice communications, it became suddenly scarce when faced with a global abundance of computers generating data at a rate of megabits per second.
In addition, the tested system performed best with the Texas Instruments and Massachusetts Institute of Technology (TIMIT) database, with a reduction of 10% for the NIST 2002 database, and approximately 30% with the telephone bandwidth version of TIMIT, or Network TIMIT (NTIMIT).
The lines use extra bandwidth in copper phone lines but still require special modems and special installation service involving a local telephone company.
Another study applied speech watermarking to enhance the intelligibility and quality of speech by extending the bandwidth of the public switched telephone network (PSTN), which is in the 200- to 3500-Hz range [19].
