Polar modulators include a
phase splitter, a controller, variable current sources,
transistor circuits, and a combiner. The
phase splitter splits a RF
carrier signal into quadrature component signals that are 90 degrees
out of phase with each other. The controller generates modulation control signals based on information that is to be transmitted. The variable current sources each generate a variable amplitude current
signal based on a different one of the modulation control signals. Each of the
transistor circuits amplify a different one of the quadrature component signals with a variable amplification based on the variable amplitude current
signal from a different one of the variable current sources to generate an amplitude adjusted quadrature component
signal. The combiner combines the amplitude adjusted quadrature component signals from each of the
transistor circuits to generate a phase-modulated RF carrier output signal.