IS4S Delivers on Resilient Software-Defined Radio in GNSS-Challenged Environments

Huntsville, AL 

IS4S was awarded a Phase II SBIR contract by the Armament Directorate of the Air Force Life Cycle Management Center (AFLCMC) to develop a resilient software-defined radio (R-SDR) that integrates a variety of complementary positioning, navigation, and timing (PNT) solutions, including signals of opportunity, with onboard sensors to enable dependable operations in contested, degraded, and denied environments. This effort follows other such contract awards from AFLCMC, most notably their selection of IS4S to lead the Resilient-Embedded Global Positioning/Inertial Navigation System (R-EGI) program.  

“We’ve been able to leverage significant advances in R-EGI, as well as our previously developed vector tracking receiver (VTRx) to meet aggressive schedule and cost requirements,” said Dr. Mikel Miller, VP for PNT at IS4S. “The open-source plugin architecture we developed for the US government has also positioned us with a robust sensor fusion capability.”  

Work began this month to integrate the IS4S-developed R-EGI/pntOS architecture with the company’s second generation VTRx SDR to fit inside a VNX+ small form factor and meet the size, weight, and power requirements of sensor open systems architecture (SOSA) 2.0, the latest industry standard for embedded computing. This form factor will enable the R-SDR to give the warfighter needed technology to gain a tactical advantage. 

“Since VNX+ is an emerging standard with many of its governing documents still in draft, we partnered with Antara Teknik to ensure access to the latest standards and requirements trends,” said Dr. Nate Smith, VP for Air Force programs at IS4S. “Antara Teknik is an industry leader in the VNX+ form factor, ideally suited to develop the backplane of the R-SDR and ensure VNX+/VITA 90.0 system compliance.”  

To reduce size and enhance navigation capability, the R-SDR features pntOS and the VTRx SDR on the same system-in-package (SiP), with pntOS being the key access and integration point for complementary, organic, and onboard PNT data. Additionally, the R-SDR enables robust communication, sending signals while the VTRx receives PNT signals from the same SiP without disruption of the PNT solution.  

R-SDR was successfully demonstrated in July 2023, just 11 short months after IS4S received the Phase II SBIR award. This proof of concept may lead to other efforts that build on this small-form-factor technology.