VOICE COMMUNICATION APPARATUS, AND METHOD FOR CONTROLLING TRANSMISSION FREQUENCY CHARACTERISTICS USED FOR THE VOICE COMMUNICATION APPARATUS

PROBLEM TO BE SOLVED: To provide a voice communication apparatus by which an acoustic echo is reduced while maintaining the feeling of volume of transmission, when two-way voice communication is performed. SOLUTION: An analog voice signal sa to be output from a microphone 17 is converted into a digital voice signal sd by an A/D converter 18; a signal level equal to or more than a first set frequency is attenuated to the digital sound signal sd by a predetermined amount by a digital filter 19; and a signal level under a second frequency set as lower than the first frequency is increased by the predetermined amount. In the first frequency, for example, 2 kHz is set, and the second frequency is set, for example, to 1 kHz, and the signal level under the second frequency is increased by the predetermined amount, by using the maximum set signal level (for example, 10 dB) as an upper limit value. In addition, the absolute value of the attenuation amount of the signal level equal to or more than the first frequency is set substantially to the same as the absolute value of the increased amount of the signal level less than the second frequency. COPYRIGHT: (C)2010,JPO&INPIT