A Large Amplitude Fourier Synthesizer Derived from the Optical Frequency Comb

5G millimeter-wave integrated circuits present new challenges for characterization to optimize energy efficiency and performance. Traditional arbitrary-waveform generation and nonlinear microwave measurement struggle to cover all the millimeter-wave bands becoming available for 5G wireless communications. Optically-derived sources are a potential path to generate arbitrary waveforms up to terahertz frequencies with extremely low noise. In this work, we demonstrate optically-derived continuous-wave signals with fine phase and amplitude control at (24.8, 49.6, 74.4, 99.2) GHz, within or near new 5G bands. Our approach begins with a 1550 nm electro-optic frequency comb that provides synchronized-optical tones across more than a terahertz of bandwidth. A programmable spectral filter applies optical amplitude and phase shifts to individual tones from the optical frequency comb. An on-wafer photodiode then converts this optical signal to large-amplitude millimeter-waves with phase and amplitude control. In this way, we demonstrate electronic phase control in 25 milliradian steps and electronic-amplitude control in 0.1 dB steps and then apply this control to additive waveform synthesis. We demonstrate optically-derived arbitrary repetitive waveform synthesis with 24.8 GHz repetition rate and up to 100 GHz of instantaneous bandwidth.