On the IF spectral placement of bandpass sampled signals

Bandpass sampling is a widely used approach to sample a continuous-time bandpass signal, and in so doing, downconvert the signal to a lower intermediate frequency (IF). To date, only a nonlinear relationship between the sampling frequency and IF has been presented. In this paper, a linear relationship between the sampling frequency and IF is derived. Since it is linear, the new finding can be used in more applications than the nonlinear relationship, including those where the IF is of importance. To illustrate this, its usefulness in applications including receiver design and carrier aggregation is discussed.