LabVIEW Signal Processing

1 Background

Sampling Signals

To use digital signal processing techniques, you must first convert an analog signal into its digital representation. In practice, this is implemented by using an Analog-to-Digital (A/D) converter. Consider an analog signal x(t) that is sampled every Δt seconds. The time interval Δt is known as the sampling interval or sampling period. Its reciprocal, 1/Δt, is known as the sampling frequency, with units of samples/second. Each of the discrete values of x(t) at t = 0, Δt, 2Δt, 3Δt, and so forth, is known as a sample. Thus, x(0), x(Δt), x(2Δt),…, are all samples. The signal x(t) can thus be represented by the discrete set of samples

{x(0), x(Δt), x(2Δt), x(3Δt),…, x(kΔt),…}

Figure 1-1 shows an analog signal and its ...