Ultra-low Size Weight and Power-Cost (SWAP-c) Tactical Free Space Optical Communication System

The US Army desperately requires wideband secure communications links in contested radio frequency (RF) environments. This capability offers tactical advantage to many platforms, including between dismounted soldiers, unmanned aerial vehicles (UAV’s), and high-speed ground platforms to name a few. Free-space optical (FSO) communications is a natural alternative to RF communications due to its inherent directional nature ensuring low probability of detection and interception (LPD/LPI), its small electromagnetic footprint, immunity from conventional RF jamming, and its high bandwidth. Despite these benefits, there are many practical reasons why FSO communication systems are not currently deployed. Chief among them are technical challenges associated with reducing the size, weight, power, and overall cost (SWaP-C) of FSO links while retaining the pointing, acquisition, and tracking (PAT) functions necessary to maintain uninterrupted communications from mobile platform. E.g. the conventional hybrid FSO solution of coarse beam steering via a gimballed telescope and fine steering via a fast steering mirror (FSM) often leads to large, power-hungry, and expensive systems which degrade over time, require maintenance, and are not justifiable for use with platforms below a certain size.  Critical Frequency Design proposes overcoming these challenges with a novel non-mechanical beam steering approach.