Abstract: In a portable communication device (100) operated in a speakerphone mode, when no speech is present in either the outbound signal received from a communication system, the speaker (114) of the communication device is muted and the microphone (120) activated. When speech is detected in an inbound signal (202, 204, 206), and speech is also subsequently detected in the outbound signal (214), the speaker is left inactivated and the microphone kept in an activated state. To determine if speech is present in the inbound signal, the inbound signal is voided, providing a succession of frames (206), each frame having a frame energy parameter and a background noise parameter (208). If the frame energy of a given frame sufficiently exceeds the an average background noise value for the given frame, then speech is declared present.

Abstract: In a portable communication device (104) that is able to operate in a speakerphone mode, a user interface such as a keypad (120) and display (122) are provided to allow the user to select (1104) an enhanced mode so that leading fricatives of speech are more likely to be detected as speech, and played over a speaker (214). Upon selecting the enhanced mode of operation, the voicing value of each frame of vocoded speech received is increased, thus making it more likely for energetic fricative frames to be detected as speech.