ABSTRArnThis paper describes the Voice Activity Detector standardised by CE€T for use in the Pan-European Digital Cellular Mobile Telephone Service. The difficulties of detecting speech in a noisy environment are discussed and the performance tests carried out to validate the design are described.

No abstract

No abstract

British Telecom International is to introduce an aeronautical telephone service to be known as the Skyphone. This service will use 9.6 kbit/s speech codecs because of the limited satellite power available. The codec to be used will be chosen from a number of codecs developed in several different countries. This paper gives a brief description of the Skyphone and the factors which influence the speech codec design. It then describes the codec proposed by British Telecom Research Laboratories as a candidate for the service. Subjective test results show this codec to be better than the other candidates declared to date.

No abstract