An example communication system includes a frequency-segmented power amplifier (PA) circuit that includes a plurality of PA segments. Each PA segment is configured to amplify a portion of a PA input signal in a different frequency band to generate a respective output signal (PA segment output signal). The frequency-segmented PA circuit further includes a combiner, configured to combine PA segment output signals from different PA segments to provide a power-amplified version of the PA input signal. Implementing such a frequency-segmented PA circuit may result in significant improvement in PA efficiency.