Techniques, systems, architectures, and methods for providing improved feature detection of signals, especially those in relatively high interference regions, thereby allowing for earlier and longer range detection of communications and radar signals are herein provided. The techniques utilize a general framework of total variation denoising, where signals are assumed to be sparse in a combination of their first or higher order derivatives, to increase signal-to-interference ratio, which is followed by cyclostationarity detection, which is used to estimate signal features, including the period of the signals of interest and their modulation type.