CC BY 4.0Gläsel, JonasJonasGläselBoerma, HendrikHendrikBoermaTran, Trung ThanhTrung ThanhTranBerisha, ArbnorArbnorBerishaBalskus, KarolisKarolisBalskusFernandes, EdgarEdgarFernandesRudin, BenjaminBenjaminRudinEmaury, FlorianFlorianEmauryRunge, PatrickPatrickRungeSchell, MartinMartinSchell2025-12-022025-12-022026https://publica.fraunhofer.de/handle/publica/500002https://doi.org/10.24406/publica-665410.1109/JLT.2025.363209510.24406/publica-66542-s2.0-105021498032We present a microwave photonic RF comb generator based on a quartz-stabilized, ultra-low phase noise fs pulse laser in combination with high-speed RF waveguide coupled photodetectors. With 325 GHz, the cutoff frequency of the subsystem exceeds the state of the art and enables broadband microwave comb generation with 1 GHz spacing in the D- and J band, when changing the photodetector from a WR6.5 to a WR3.4 device. We generate microwave tones at 270 GHz with a phase noise of -81 dBc/Hz at 1 kHz frequency offset and below -130 dBc/Hz at 1 MHz offset while achieving a spectral width below 1.7 Hz in the electrical domain.entrueD-bandfs-pulse laserhigh-speed photodetectorJ-bandmicrowave photonicsoptical frequency combphase noisejournal article