Advancing capabilities for deployable USRPs
The USRP and Military Embedded Systems
The inception of the Universal Software Radio Peripheral (USRP) was rooted in connecting standard computer hardware to the electromagnetic spectrum to enable rapid wireless development and real-world experimentation. We are now in the second decade of the USRP evolution and SDR technology has permeated many applications and industries. USRPs have been a critical tool for engineers building novel communications, sensing, and EW algorithms.
The USRP is very attractive to developers, with good analog performance as well as a vibrant community of open-source software developers to collaborate and draw from. In the defense space, after a capability is proven, users are often required to port their designs onto mission hardware for final deployment. This step of migrating platforms, to some, has been seen as an unnecessary engineering step and a risk leading some to develop and prototype directly on mission hardware. A key customer once said, “I love these USRPs, but I just can’t fly them”; this was pointing out the truth that most USRPs are not designed for harsh environmental conditions and are not built to deploy like standard, ruggedized military embedded systems. Some users have innovated in this space and have built fully ruggedized enclosures as SkySafe did with their innovative drone defense solution. Some have built specialized enclosures for the USRP like the RX310 from Pixus Technologies.
Standardization in Military Embedded Systems
In the same decade that the USRP was evolving, developers of military embedded systems were in the process of migrating from the legacy VME platform to the open and higher performance VITA 65 standard in VPX. However, VPX – while amazingly powerful and flexible – proved too open and led to many proprietary systems with limited interoperability. In 2017 at the Embedded Tech Trends event in New Orleans, an effort was proposed to standardize and limit the number of backplane configurations for VPX to reduce the proprietary nature of systems, lower cost, and get the capability to the defense branches faster. As such, a tri-service effort was born with The Open Group Sensor Open Systems Architecture™ (SOSA). Today the US Army, Navy, and Air Force have committed to the open platform approach to military embedded systems and have agreed to require future sensors, communications, and EW systems to be aligned to the SOSA technical standard. As noted by John McHale in the recent release of the SOSA 1.0 special edition at AUSA 2021, the vision of a truly open standard is more than just hope now.
A faster way to deploy new capabilities
To date, there has been a large gap between what is being driven by the standardizations of VPX and what developers are able to achieve with the most popular SDR, the NI / Ettus Research USRP.
In 2019 at the Association of the US Army (AUSA) event in Washington DC, an idea was born that if USRP had a SOSA-aligned 3U VPX version, it would significantly benefit the defense services and give developers a path to deployment.
A conversation that started on the expo floor turned into a collaboration between NI and Curtiss-Wright Defense Solutions to take the popular USRP E320 and port it directly to 3U VPX. At the AUSA 2021 event, the first step in this collaboration was revealed with the VPX3-E320 Ruggedized Universal Software Defined Radio. The new VPX3-E320 is SOSA aligned and fully compatible with the USRP Hardware Driver (UHD). This interoperability allows development with the Ettus Research USRP E320 on more engineer’s desks than was possible with developing on a full mission system hardware. Furthermore, the development built on the USRP E320 code can be directly run on the VPX3-E320 in a matter of seconds.
No longer is the USRP limited to the lab or custom enclosures. With the NI / Curtiss-Wright collaboration, development teams can test systems in parallel, improving development efficiency, and reducing the risk of porting to mission hardware with the first fully rugged SOSA-aligned VPX universal software-defined radio from Curtiss-Wright Defense Solutions.