Military service members depend on a growing number of electronic functions, including communications, electronic warfare (EW), and radar. Defense OEMs face increasingly complex challenges in supplying solutions for these electronic functions due to an ever-increasing demand for size, weight, power, and cost (SWaP-C) reduction. These challenging requirements set the stage for the innovative use of new technologies. Benchmark Lark Technology addresses these requirements through our technology roadmap for electronic miniaturization, microelectronics, millimeter-wave (mmWave) systems, and photonics capabilities. These investments let us help our customers create electronic solutions for military communications, EW, and radar that are smaller, lighter, and operate with less power but provide higher performance than previous-generation devices and assemblies.
In July of this year, I had the opportunity to participate in the Microwave Journal online panel session, "The Future of EW, Radar, and Communications Systems," with fellow engineers working in military electronics. We share an interest in meeting difficult SWaP-C requirements for military communications, EW, and radar systems often operating well into the mmWave frequency range. These engineers are actively developing military electronic systems that are smaller, lighter, and less power-hungry than in the past and "smarter" or more functional while working at higher frequencies.
I shared insights into the manufacturing processes and design strategies that make these emerging systems a reality. In pursuit of SWAP-C requirements, the printed circuit board (PCB) dimensions are intricately detailed, almost like the dimensions of semiconductors several decades earlier. At Lark, we pursue challenging miniaturization goals for military electronic products, particularly the design, fabrication, and assembly of mmWave circuit assemblies. Electronic solutions for military communications, EW, and radar systems at microwave and mmWave frequencies requires highly integrated PCBs densely packed with active and passive components.
Using the Right Manufacturing "Tools" for the Job
To meet the needs of military customers for miniaturized electronic assemblies and circuits requires the right mix of manufacturing tools and an understanding of when to use them for the most significant benefit. For example, a customer recently engaged us with a high-layer-count multilayer PCB assembly that needed the same or better functionality but in a fraction of the current size.
When we take on a miniaturization project, we try to apply modern manufacturing tools that make sense for the application. Using a modified semi-additive manufacturing approach, we work with high-frequency compatible materials and additive manufacturing techniques, including multiple etching and plating steps to achieve smaller circuit feature sizes. We met this customer's miniaturization requirements with this novel manufacturing approach without sacrificing reliability or signal-loss performance.
Fully additive manufacturing is an exciting technology that some are investigating but is not yet practical for a case like this. The application of cutting-edge electronic manufacturing tools such as fully additive manufacturing with three-dimensional (3D) printers can provide dramatic reductions in the sizes of PCB assemblies but, for this customer, predictable, known reliability and RF performance are overriding concerns. The reliability of circuit designs fabricated with full additive manufacturing techniques still leaves some room for uncertainty because of its shorter track record. Additionally, desired RF performance can be challenging since many common low-loss materials are not utilized in fully additive manufacturing processes.
Lark's experience fabricating its PCBs with high-performance dielectrics such as liquid crystal polymer (LCP), which exhibit excellent electrical characteristics, has enabled us to manufacture our advanced high-frequency system-in-package (SiP) designs. By creating circuits with fine lines and spaces, and SiP devices in place of much larger traditional assemblies, we continue to address some of the industry's most challenging requirements for miniaturization in military communications, EW, and radar systems.
A Potential SWaP-C Gamechanger: Multifunction Systems
As military users seek to use available bandwidth in the mmWave frequency range, systems integrators also seek increased functionality in smaller form factors by designing multifunction systems. By transforming two separate systems, such as radar and communications systems, into one integrated system, applications such as UAVs can take advantage of the SWaP-C benefits resulting from the increased functionality from a single system.
For electronic designers and manufacturers of such highly integrated solutions, the challenges of combining traditionally separate electrical functions extend from the choice of the antenna through the remote radio control and graphical user interface—challenges in integrating mixed-signal hardware, digital signal processing (DSP), and software. The design absolutes for advanced airborne and mobile terrestrial applications are very real and in growing volumes that require proven manufacturing processes. In many cases, successful multifunction system solutions consist of a practical blend of software and analog and digital hardware, as found in a software-defined-radio (SDR) architecture that can be applied to communications, EW, and radar areas.
Lark's experience with mixed-signal PCBs and multilayer assemblies demonstrates the importance of starting with a complete understanding of the substrate materials so that analog and digital signals are maintained with the highest signal integrity over a wide range of operating conditions. By incorporating integrated circuits, SiPs, field-programable gate arrays (FPGAs), and other miniature components that provide high performance and have been characterized for high reliability, engineers can develop compact multifunction system solutions. These integrated systems-within-systems offer the equivalent functionality and performance of formerly separate systems, with all the SWaP-C advantages while still meeting the most demanding goals for high reliability.
What's the Future of EW and Radar?
Electronic warfare and radar systems are on the verge of rapid innovation towards new capabilities, longer ranges, and improved performance. So many underlying technologies, from advances FPGAs to MIMO antennas, are overcoming limitations in existing systems. Preserving performance while improving SWaP-C is a consistent, overarching theme. With our focus on electronics densification, mmWave technology, and high-speed circuits, the Lark team is proud of our role in moving these systems forward.