System and method for speakerphone operation in a communications device

Abstract

The invention provides a cellular telephone or other communications device with intelligence to manage speakerphone operation to more nearly approximate normal conversation, even when using a one-way only transmission mode. The microphone path (128) and speaker path (130) may be continuously monitored using dual voice activity detectors (114, 118) to assess the energy and other characteristics of each channel, and switch between one or the other depending on dynamic criteria. In noisy environments, a hangtime may be applied before permitting switching to avoid premature dropouts. Other criteria used to trigger the seizure of the channel may be adjusted, such as to eliminate a lower threshold below which the speaker path (130) switches out automatically.

Description

technical field [0001] The present invention relates to the field of communications, and more particularly to techniques for clearer, more reliable hands-free phone operation in cellular telephones or other communications devices. Background technique [0002] Convenience and efficient hands-free telephone operation are desirable features in cellular handsets and other communication devices. Groups concerned with traffic safety have banned hand-held operation of cellular phones while driving under certain conditions. Cell phones and other devices equipped with hands-free phone features allow users to place the device in a stationary position in a vehicle or elsewhere while still performing normal calls and other phone access. [0003] However, equipping a cellular phone with effective hands-free telephony capabilities is not an ordinary integration exercise. One practical difficulty is that most cell phones are small devices that contain earphone speakers and integrated mi...

AI Technical Summary

Problems solved by technology

This one-way operation makes direct feedback impossible, but results in one-way communication

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