Exact Cramer-Rao Bounds for Signals with Constant Amplitude and Polynomial Phase

摘要

Exact and closed-form Cramer-Rao bounds (CRBs) are derived for parameters of a continuous-time complex signal s(t)=Se~(jphi(t)) with constant amplitude and polyomial phase of arbitrary degree.The signal is measured in additive white Gaussian noise over arbitrary time interval [T_1,T_2].The influence of changes in the measurement interval center on CRBs is analyzed and two special cases of O<=t<=T and -T/2<=t<=T/2 are considered in more detail.It is shown that the latter case,though less often used,gives lower CRBs for phase parameters.