Apparatus for enhanced voice quality in multiple cordless handset environment and method

Abstract

The present invention provides a method and system to improving voice transmission quality within an environment containing multiple off-hook cordless telephones all residing on the same subscriber line. This is achieved by coordinating the sending, receiving, and acknowledging (i.e., handshaking) of control and telephone signals between the multiple cordless telephones and the base. The communication between cordless telephones takes place through a single household telephone line and the RF link existing between each cordless handset and its accompanying base station. When a single handset of a multiple handset cordless telephone system is registered as off-hook, the handshaking between that handset and base results in the transmission of voice signals between the off-hook handset and the base which are digitized using Adaptive Differential Pulse Code Modulation (ADPCM). When one or more handsets become active and are registered as off-hook, the transmission of voice signals between the off-hook handsets and base is accomplished through the use of speech coding at a lower rate than that of ADPCM coding. The successful switching between ADPCM and speech coding within a multiple handset environment allows for speech quality to be maximized at all times.