Analog Transformation Complements Open System Designs to Optimize Modern Defense Systems

December 1, 2024

The final frontier in digital transformation is the analog edge, where apertures and actuators meet the mission. Buried behind layers of firmware and analog mitigation, open architecture has a new frontier to conquer, and the opportunity starts at the component level, where digital transformation and the miniaturization enabled by Moore’s Law is having its biggest impact.

Miniature, modular, and intelligent gateways can be embedded into analog components to replace and re-imagine old firmware and analog mitigation circuitry. These new, embedded gateways promise to bring open architecture deeper into the tactical edge and realize a new level of agility throughout the lifecycle of a system, from design through sustainment of hybrid digital and analog systems.

This analog transformation supports the U.S. Department of Defense (DoD) emphasis on modularity, flexibility, and affordability embodied by its Modular Open Systems Approach (MOSA) mandate. It also allows the modern military to best address ever-evolving threats, as it will allow for quick, efficient, and effective system enhancements.

Open, interoperable systems are now considered essential to the future of more agile weapons systems. They create greater design options, shorten development cycles, and help control costs. Open systems also simplify adaptability and project updates, as well as make them more efficient.

Analog transformation is the key to fully realizing these benefits and to better achieve the DoD stated goals for modern weapons systems. RF and digital technologies must be synergistically developed and integrated at the onset, which will lead to optimized flexibility, affordability, and modularity.

Defense Systems for Modern Battlefield

Re-imagining component design along with support for open architectures serves as a foundation for modular solutions that embed various digital signal processing (DSP) elements and single board computers (SBCs) inside analog functions. Advanced capabilities can be efficiently added into numerous systems, including:

• Electronic Warfare (EW) – Small platforms, such as Unmanned Aerial Systems (UAS), previously somewhat limited due to size, weight, power, and cost (SWaP-C) constraints, will become increasingly prominent.

• Command, Control, Communications, Computers, Cyber, Intelligence, Surveillance and Reconnaissance (C5ISR) - Joint C2 platforms, secure communication networks, and real-time analysis systems can reach their full potential.

• Radar - Multi-Function Radar (MFR), Phased Array Radar, and other radar systems can be better designed to meet the demands of the modern battlefield.

Modularity and Standardization

A cornerstone of the DoD’s strategy is the Sensor Open Systems Architecture (SOSA™). It uses modular hardware plug-in card profiles (PICPs), such as 3U and 6U VPX, to allow various sensor components, including RF, signal processing, and computing modules, to be integrated into a single, standardized chassis. By enabling components to be easily swapped or upgraded without redesigning the entire system, SOSA eliminates the need for multiple mission footprints and associated custom engineering and platforms to facilitate mission-specific outcomes.

Simultaneously, systems utilizing open architectures can be easily scaled up by adding more modules, as necessary. Such flexibility allows defense contractors to design systems that meet current needs without over-investing in unnecessary capacity.

SOSA is made possible by the on-going digital transformation of everything, which is an accelerating opportunity to bring a new level of mass affordability and adaptability to DoD missions. A remaining frontier to exploiting this trend is analog transformation.

Other Defense System Design Drivers

While a SOSA-based open architecture is a key driver of smaller, modular, and cost-efficient defense systems, it is not the only one. To fully achieve the DoD stated goals, a fundamental re-envisioning of analog components and systems is necessary. Digital functions need to be integrated into analog devices to optimize and streamline system development.

The direct digital sampling revolution at the analog edge is bringing the promise of digital transformation ever closer to the tactical edge. It will not eliminate the need for all analog functions. It can, however, replace the need for numerous analog conversion and mitigation functions with digital, auto tuning, conversion functions and capabilities. SOSA is a forcing function for this transition and important tool to make the analog edge more adaptable and flexible. The result leads to automated test and tuning functions, enabling real-time adaptability on the battlefield.

This analog transformation can be referred to as a digital gateway (figure 1). It creates a more efficient design path for SOSA-aligned products. An open-standard, building block approach with ultra-miniature, wideband RF capability and an integral digital gateway establishes numerous benefits. They can be used to realize more agile defense subsystems, systems, and systems-of-systems. The building block design with standard interfaces can dramatically shorten lead times, as well.

SOSA-compliant Building Block Solutions

SOSA-compliant digital gateway building blocks are the cornerstones of next-generation RF solutions that address the SWaP-C and open architecture requirements of emerging military and aerospace system designs. Key innovations using Field Programmable Gate Array (FPGA) technology and 2.5D manufacturing are enabling a no-compromise improvement in digital enablement without affecting size, weight, power, or performance.

Currently, high density, high fidelity, wideband RF solutions can be developed at three levels – SOSA-aligned VPX modules, as well as system in package chips (RF SiPs) and integrated mezzanine boards that slide into a standard chassis/ backplane. Each offers a dramatic SWaP reduction and an open-standard digital interface for tuning, monitoring, and control. System integration is also dramatically simplified.

RF VPX modules, such as the one shown in figure 2, align with SOSA. The modularity embedded in the architecture allows for various combinations of upconverters or downconverters in a 3U OpenVPX form factor that supports various mission configurations. Repeatable, high performance without the need for manual tuning is achieved.

Advanced FPGA Technology

Such SOSA-aligned wideband module platforms leverage FPGAs to add direct digitization. Advanced FPGAs provide a step function improvement in digital modularity and interoperability in RF systems with the revolutionary inclusion of analog-to-digital conversion and processing.

The modularity and channel control of the architecture is designed to manage the integration of digital and analog technologies into a high-performance, single-slot solution. As critical functions shrink, further SWaP-C improvements can be achieved to support new mission parameters. They can also create space for added software functionality and eventually artificial intelligence (AI).

SOSA-compliant systems such as those outlined here are designed for easier upgrades. When technology evolves, only specific modules need to be updated or replaced, rather than the entire system. This allows for cost-efficient updates without having to overhaul the entire platform.

Conclusion

The development of SOSA Technical Standard 1.0 nearly three years ago has led to a growing number of open architecture designs that are enabling more rapid development of system capabilities that satisfy SWaP-C mandates from the DoD. New RF building blocks that implement a digital gateway to provide digital functionality in analog components while leveraging RF fidelity further advance defense systems to meet requirements of modern warfare.

This article was written by Ian Dunn, Chief Technology Officer, Spectrum Control (Fairview, PA). For more information, visit here  .

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