Vescent has developed a prototype ultra-stable microwave photonic oscillator capable of advancing the dual DoD and non-DoD needs for alternative positioning, navigation and timing (aPNT), multi-static synthetic aperture radar (SAR), 5G-and-beyond wireless communication, satellite synchronization, and geodetic sensing. Due to shortcomings in sensitivity, dynamic range, and/or resolution, current microwave oscillators for radar limit the identification and tracking of objects with small radar cross sections, including slow-moving objects such as drones. These limitations are dominated by the microwave oscillator phase noise and/or instability. Vescent’s photonic microwave source exploits the method of optical frequency division to transfer the pristine phase noise properties of an ultranarrow linewidth optical laser to microwaves in the L-, C-, or X-band for sensing and imaging. Efforts to improve the long-term frequency stability required in communications and timing synchronization will be discussed. The environmental performance of several key subsystems will also be considered with pathways to reduced size, weight, and power (SWaP). Finally, performance improvements related to the long-term stability of this system will be discussed to simultaneously provide both ultralow phase noise comparable to the best deployable microwave oscillators available and low frequency instability for communication and timing synchronization at a drastically reduced SWaP and environmental susceptibility.
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