Gardner The cyclostationarity property of communications and telemetry signals enables the generation of spectral lines with appropriate nonlinear transformations, and renders fluctuations in distinct spectral bands statistically dependent. The frequencies at which spectral lines can be generated are directly related to the separations between dependent spectral bands, which in turn are directly related to carrier frequencies, keying rates, pulse rates, and so on, in the signal. These inherent properties of cyclostationary signals can be exploited to great advantage for numerous tasks in signal processing. The objectives of this research are: 1. to investigate new cyclostationarity-exploiting methods for identifying the kernels in the Volterra series representation of time-invariant and multiply-periodic time-variant nonlinear systems; and 2. to further develop the recently introduced cyclic temporal and spectral moment and cumulant theory of higher-order cyclostationarity, with application to designing higher-order spectral-line generators for signal detection and identification, and for signal parameter estimation and synchronization.