What is VCO in GNU Radio?
VCO - Voltage controlled oscillator. Produces a sinusoid of frequency based on the amplitude of the input. See VCO (complex) for a complex sinusoidal output. input: float stream of control voltages; output: float oscillator output.
How does GNU radio work?
GNU Radio is a free & open-source software development toolkit that provides signal processing blocks to implement software radios. It can be used with readily-available low-cost external RF hardware to create software-defined radios, or without hardware in a simulation-like environment.