LOW-RATE SPEECH CODER FOR NON-SPEECH DATA TRANSMISSION

摘要

Low rate data signals, such as standard TTY signals and standard DTMF signals, can be effectively analyzed and encoded by speech encoders employed in conventional digital cellular system. This is accomplished by providing a low rate data encoder in the transmission path of the low rate data signal, just prior to the speech encoder used by the digital cellular system. In so doing, the standard, low rate data signal is transformed (i.e., modified) by the low rate data encoder into a signal that is more compatible with the speech encoder. Similarly, a low rate data decoder is provided at the receiving end of the transmission path to decode the modified, low rate data signal.