The power spectral density of multiuser continuous phase modulation systems

The calculation of power spectral density for multiuser continuous phase modulation systems is discussed thoroughly in this paper. The method is a generalization of the autocorrelation function method successfully used in single user systems, which leads to a closed-form expression for multiuser systems. Based on this result, the bandwidth is defined and an approximation is proposed to simplify the calculations in practice. Some properties of the power spectral density are observed, one of which reveals the near-far phenomenon in the frequency domain.