Inside a laser system’s fiber-optic cabling is a power-limiting challenge known as Stimulated Brillouin Scattering (SBS). Driven by high-power environments, SBS triggers a reflected light beam (Stokes wave) that threatens the integrity of system components.
Directed energy weapons (DEW) must operate at high power, but this requirement is the catalyst behind SBS. To find a solution, engineers need to look no further than additive white Gaussian noise (AWGN) generation.
Referred to as coherence spreading, a random AWGN signal can modify the phase of the optical wave, leaving the peak amplitude and frequency unaltered. Dispersing peak power reduces SBS and maintaining average power enables an extreme power output.
This post explores how engineers can tackle SBS challenges with AWGN during laser weapon design.
While in the lab, engineers need to figure out the exact AWGN output that optimally mitigates SBS for their specific laser system. The ideal AWGN generator must be able to grant the freedom that DEW design demands. A couple key instrument features include:
The path toward finalizing specs for SBS reduction is through utilizing an extremely flexible AWGN generator that offers a high degree of noise control. Engineers can manipulate attenuation, amplification, and filtering to lock down the correct noise frequency bands and power levels. The unique noise signal is fed directly through the laser’s optical phase modulator.
Watch the video below for an inside look at a versatile AWGN generator and how it connects to a DEW under test.
💡Did you know that what’s best for DEW during design is different than DEW ready for the field? Read our blog post on how the NC1000 Series is ideal for DEW primed for deployment.
During DEW development, evaluation moves from a regulated lab setting to test chambers that replicate real-world conditions. Engineers analyze the system’s performance when subjected to temperature, vibration, altitude, moisture, and other simulated effects. In order to dynamically adjust the AWGN signal, engineers must be able to control the instrument remotely.
The UFX7000B Series Programmable AWGN Generator from Noisecom offers these essential capabilities, enabling the design of DEW that operate at the highest level of performance.
The Noisecom UFX7000B is an extremely versatile platform that generates complex, custom AWGN signals through controllable attenuators, switches, and filter banks. Key features and specifications include attenuation over a 127 dB dynamic range in 0.1 dB steps, signal amplification up to +30 dBm, frequency bands up to 40 GHz, and band limitation via various filter paths.
If a DEW has moved into the test chamber phase to see how it fares against strenuous simulated conditions, users can switch from manual touch screen control of the UFX7000B to remote use through Ethernet or GPIB connections. With flexibility at its core, the instrument is highly customizable to satisfy the unique demands of each laser weapon and its intended application.
Want to learn more about AWGN solutions for DEW beyond the design phase? Our blog features posts about an ideal noise source for deployment-ready systems as well as a complete overview on how to enhance DEW design and deployment with noise generation.
The Noisecom solutions guide and applications note are also excellent resources to learn how you can design and deploy the best high energy laser possible via AWGN-backed coherence spreading.
Choose high-performance noise sources from Noisecom to simplify design and ensure DEW are optimized from the start.