Digital to analog converter using B spline function

The digital-analog converter, comprising:

• a sampling function generation unit continuously generating an analog signal waveform corresponding to a sampling function of local support;
• and
• a first generation unit shifting a generation time of the sampling function corresponding to each of n pieces of digital data sequentially input at predetermined intervals, amplifying the sampling function before or after the shift by a gain depending on a value of the corresponding digital data, and generating a signal by adding up amplified outputs in an analog algorithm,
• wherein said sampling function generation unit which continuously generates a signal waveform corresponding to said sampling function, comprises:
• a B spline function generation unit continuously generating a signal waveform corresponding to a B spline functions;
• a second generation unit generating a signal waveform by adding an ancillary waveform obtained by attenuating and polarity-inverting a basic waveform before and after the basic waveform on a time axis when a signal waveform output from said B spline function generation unit is deffined as the basic waveform.