| 摘要 |
<p>In a headset worn on a user, a user's voice is input to a microphone, and a controller compares an output signal of the microphone and first reference data, and the telephone is set off the hook by the output of the control section. During speech, the controller compares speech data and second reference data, and changes a gain of a second amplifier for driving a loudspeaker according to the difference between the data. When a volume of each of partner's voice and user's voice is smaller than a predetermined volume, the controller outputs a warning sound from the loudspeaker. After a predetermined time lapses, the telephone is set back on hook. In a communication system including the headset and telephone, the headset does not require a speech switch, a voice-volume-increase switch, or a voice-volume-decrease switch. Preferably the headset is a wireless headset using the Bluetooth standard.</p> |
