This paper addresses the cost, signal integrity and I/O bandwidth problems in radio-frequency testing by proposing a feature extraction based built-in alternate test scheme. The scheme is suitable for built-in self-test of radio-frequency components embedded in a system with available digital signal processing resources, and can also be extended to implement built-in test solutions for individual RF devices that have access to a low-end digital tester. The process applies an alternate test and automatically extracts features from the component response to predict specifications like third order intercept point, 1dB compression point, noise figure, gain and power supply rejection ratio. The proposed scheme makes use of low-speed low-resolution undersampling to eliminate the need for a bulky analog-to-digital converter and the use of a noise reference for comparison makes it possible to compensate for imperfect stimulus generation. The simulation results for a 1 GHz downconversion mixer and a 900 MHz low-noise amplifier present an average of 97.3% prediction accuracy of specifications under test.