  Cyclic spectral analysis is a signal processing technique designed to deal
with stochastic signals whose statistics vary periodically with time. Pulsar
radio emission is a textbook example of this signal class, known as
cyclostationary signals. In this paper, we discuss the application of cyclic
spectral analysis methods to pulsar data, and compare the results with the
traditional filterbank approaches used for almost all pulsar observations to
date. In contrast to standard methods, the cyclic spectrum preserves phase
information of the radio signal. This feature allows us to determine the
impulse response of the interstellar medium and the intrinsic, unscattered
pulse profile directly from a single observation. We illustrate these new
analysis techniques using real data from an observation of the millisecond
pulsar B1937+21.
