Transmitter and method for transmitting and receiving of voice data for VoIP service

A voice data receiving method for providing a VoIP service, comprising:

• receiving a plurality of voice data packets, each having a time indication bit that is changed every transmission period inserted therein;
• storing first voice data demodulated from a first voice data packet of which a time indication bit inserted therein corresponds to a current transmission period among the plurality of voice data packets in a first buffer;
• storing second voice data demodulated from a second voice data packet of which a time indication bit inserted therein is different from the current transmission period and is received after a reference time among the plurality of voice data packets in a second buffer;
• interpolating the voice data stored in the first buffer;
• converting the interpolated voice data into an analog signal;
• and
• outputting a voice signal by filtering the analog signal.

A transmitting apparatus for providing a VoIP service, comprising:

• a voice signal detection unit that detects a voice signal from an input analog signal;
• a plurality of sampling units that output a plurality of sampled signals that are sampled with different phases in the same frequency from the analog signal when the voice signal is detected in the voice signal detection unit;
• an analog to digital converter (ADC) that converts the plurality of sampled signals to digital signals and outputs a plurality of voice data;
• and
• a plurality of modulators that modulate the plurality of voice data and generate a plurality of voice data packets, insert the plurality of voice data packets in a transmission frame and transmit the transmission frame,
• wherein, in the sampling of the analog signal, a phase difference between the plurality of sampled signals is set to correspond to a value obtained by dividing a sampling period by a number of voice data packets generated every sampling period.