High Dynamic Range, Low Noise Optical Link for Reduced SWaP

High fidelity communication networks within a naval vessel is a critical need for the warfighter. The ability to transport and distribute radio frequency (RF) signals from antenna arrays located throughout the ship to Wideband Anti-jam Modem System (WAMS) enables critical systems to receive and transmit information required to maintain the safety of the crew. Currently, RF signals are distributed from antenna to receiver by a microwave waveguide. This method of communicating is highly loss, expensive, difficult to maintain. Enabled by recent technological developments of the past two decades, silicon microwave photonics offers a promising alternative to transporting and distributing high-speed RF signals. As proven by the ubiquitous implementation of fiber optic networks as the backbone of our modern internet, photonic links offer high bandwidth, high dynamic range, and low loss. At 40 GHz, a typical RF cable optimized for low attenuation operates at 2.95 dB per meter compared to a fiber optic cable which has an RF attenuation of 1 dB per kilometer. Additionally, fibers are fraction of the price with regards to materials and maintenance. Transitioning to optical communication networks allows for the implementation of wavelength division multiplexing resulting in one optical cable transporting THz of RF signals over many wavelengths of light within the C-band. While the fiber optic systems which enable the internet are digital, analog photonic links have been in development equally as long and offer the same benefits. These systems were not adapted as quickly as their digital counterparts due to the relatively high noise figure and cost of discrete analog photonic links. While device and architectural research has incremental improvements to these RF metrics over the past three decades, the breakthrough development, standardization, and commercialization of photonic integration, specifically silicon photonics, has resulted in orders of magnitude improvements in size, weight and power (SWaP), RF performance metrics, and cost.