Constellation design for PAM in presence of imperfect Doppler frequency shift estimation

This paper discusses the effect of imperfect Doppler frequency shift estimation on communication system performance from a view of information theory. As a result, estimation error can cause the loss of mutual information between input and output signal. Besides, a novel scheme of signal constellation for pulse amplitude modulation (PAM) is proposed, which is more robust against the frequency offset estimation error, since the intervals of points in this constellation are redistributed based on the principle of maximizing minimum guard interval. Both theoretical analysis and numerical simulation prove that this new system design has a better performance than the conventional one.