DIGITAL MOBILE TELEPHONE COMMUNICATION METHOD, SPEECH CHANNEL SWITCHING METHOD AND MOBILE STATION AND BASE STATION TO REALIZE THE METHODS

摘要

PURPOSE: To attain accurate measurement of quality of a speech channel in operation and to simultaneously transmit voice information and character information using one speech channel by inserting a data signal in place of a digitized voice signal for a silence period at a transmitter side. CONSTITUTION: A voice detection section 44 detects a silence block between voice signals and controls a selector 18 to allow the selector 18 to select the output of a silence notice frame generating section 46 and a PN pattern data generating section 48 for the silence block. A silence notice frame is made up of a start signal inserted to a head of PN pattern data and an end signal inserted to the end. A silence notice frame detection section 50 detects the start signal and the end signal from a burst signal outputted from a TDMA section 34 to recognize the start and the end of PN pattern data and allows a PN pattern detection section 52 to detect a bit error in the received PN pattern data and controls a selector 36 to select a digitized voice signal equivalent to a silence for background noise from a background noise insert section 54.