Patent · US Expired

Method and apparatus for improving the voice quality of tandemed vocoders

US5995923A · kind A · utility

83Cited by
8References
35Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 26, 1997
Grant dateNov 30, 1999
Priority date
Expiry dateJun 26, 2017

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04W88/181
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

In recent years, the telecommunications industry has witnessed the proliferation of a variety of digital vocoders in order to meet bandwidth demands of different wireline and wireless communication systems. The rapid growth in the diversity of networks and the number of users of such networks is increasing the number of instances where two vocoders are placed in tandem to serve a single connection. Such arrangements of low bit-rate codecs can degrade the quality of the transmitted speech. To overcome this problem the invention provides a novel method and an apparatus for transmitting digitized voice signals in the wireless communications environment. The apparatus is capable of converting a compressed speech signal from one format to another format via an intermediate common format, thus avoiding the necessity to successively de-compress voice data to a PCM type digitization and then recompress the voice data.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.