The output signal x ( t ) from the sensor is an analog signal that is continuous with time.
But the signal is discretised when it is acquired by computer through an interface. This digital signal is a series of discrete data 
obtained by measuring (called sampling) an analog signal instantly at every time interval 
and is given as 
where n is an integer.
This interval is called a sampling interval. A digital signal is descretised in both time and magnitude. Discretization in magnitude is called quantization, and the magnitude is represented by binary numbers (unit: bits). Digital data in a personal computer are processed into various forms using software programs. In this operation, two representative processing are performed. One is signal extraction , where unnecessary signal components are abandoned in the acquired data, and the other is data transformation , where the data are converted to a convenient form.
obtained by measuring (called sampling) an analog signal instantly at every time interval and is given as where n is an integer.
This interval is called a sampling interval. A digital signal is descretised in both time and magnitude. Discretization in magnitude is called quantization, and the magnitude is represented by binary numbers (unit: bits). Digital data in a personal computer are processed into various forms using software programs. In this operation, two representative processing are performed. One is signal extraction , where unnecessary signal components are abandoned in the acquired data, and the other is data transformation , where the data are converted to a convenient form.