For the Beginner at CSP

Here is a list of links to CSP Blog posts that I think are suitable for a beginner: read them in the order given.

Introduction to CSP

How to Create a Simple Cyclostationary Signal: Rectangular-Pulse BPSK

The Cyclic Autocorrelation Function

The Spectral Correlation Function

The Cyclic Autocorrelation for BPSK

The Spectral Correlation Function for BPSK

The Frequency-Smoothing Method of Spectral Correlation Estimation

The Time-Smoothing Method of Spectral Correlation Estimation

The Spectral Coherence Function

Estimation Quality: The Resolution Product

Blind Cycle-Frequency Estimation: The SSCA

Blind Cycle-Frequency Estimation: The FAM

Computational Costs of Second-Order Estimators

The Periodogram

Signal Selectivity

The Cycle Detectors

A Gallery of Spectral Correlation

Verification Guide for Second-Order Estimation

This list leaves out all the posts on higher-order cyclostationarity, all the posts on machine learning, all the posts that present reviews of published technical papers, and a lot of advanced or niche topics. See the Highlights post for a guide to those posts, or just load and read from the bottom up!

A Gallery of Cyclic Correlations

There are some situations in which the spectral correlation function is not the preferred measure of (second-order) cyclostationarity. In these situations, the cyclic autocorrelation (non-conjugate and conjugate versions) may be much simpler to estimate and work with in terms of detector, classifier, and estimator structures. So in this post, I’m going to provide plots of the cyclic autocorrelation for each of the signals in the spectral correlation gallery post. The exceptions are those signals I called feature-rich in the spectral correlation gallery post, such as LTE and radar. Recall that such signals possess a large number of cycle frequencies, and plotting their three-dimensional spectral correlation surface is not helpful as it is difficult to interpret with the human eye. So for the cycle-frequency patterns of feature-rich signals, we’ll rely on the stem-style (cyclic-domain profile) plots in the gallery post.

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The Cycle Detectors

Let’s take a look at a class of signal-presence detectors that exploit cyclostationarity and in doing so illustrate the good things that can happen with CSP whenever cochannel interference is present, or noise models deviate from simple additive white Gaussian noise (AWGN). I’m referring to the cycle detectors, the first CSP algorithms I ever studied.

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