Dual-mode handset

A dual-mode handset is a flexible worn device that connects to more than one wireless base station, typically a cordless and cell combination. The DECT/GSM combination is expected to be particularly powerful, as it will enable broad coverage via GSM and extremely high quality audio, data, and enhanced services via DECT (where that coverage is available).

Such handsets should only be carried in the hand to "dial" (i.e. use the touchtone interface), the headset should be assumed to be in use at all other times.

audio configuration

Existing cell and cordless handsets have lousy audio and so typically only require a 1.5mm stereo jack.

A DECT connection has sufficiently high quality audio to be effectively equivalent to an FM radio, so headset quality would be about the same as a typical walkman, with a microphone good enough for MP3.

This suggests that a 2.5mm stereo headset jack would be part of the set, and might switch between receiving left and right channels of FM stereo, or receiving high-quality mono and sending (via microphone) high-quality mono. Or, it might have two separate stereo jacks the way laptops and PDAs do, and support for full stereo sound, and full stereo (two source) input.

In any case, no physical disconnection or switching would be required to shift modes. In a combined DECT/GSM network, the handover is also seamless - it is only billing that indicates the difference between which nets are used.