Dynamic Spectrum Sharing for 5G and the DoD’s Best Practices for Testing


To support the new combined 5G demand, the Department of Defense (DOD) will share its once-exclusive spectrum with commercial entities. The challenge is how defense organizations support Dynamic Spectrum Sharing (DSS) while guaranteeing secure, reliable access for essential missions. This includes how the DOD ensures the reprioritization of spectrum for defense use when there’s an urgent need.

The U.S. Department of Defense is “all in” on 5G. Defense teams are actively exploring, prototyping, and testing technologies and use cases, to harness the faster speeds, low latency, and connectivity for massive numbers of devices that comes with this fifth-generation wireless technology. From warehouses to the battlefield, 5G applications are expected to strengthen our nation’s warfighting capabilities. Of course, the civilian world is well on its way to adopting 5G as well, embracing the advantages for commercial and economic competitive advantage.

One challenge to the widespread adoption of 5G is that the higher capacity and throughput require access to more spectrum, which is already a scarce resource. Before 5G, spectrum was allocated for exclusive commercial or government use. In 2020, the DOD – one of the largest owners of U.S. spectrum – agreed to share its spectrum to support commercial 5G demand. Specifically, the DOD has a goal of making 100 MHz of the highly desired mid-band, or 3.45 GHz band, spectrum available for commercial use.

Now, the real challenge begins. How can defense organizations support DSS with commercial entities while ensuring the secure, reliable access they need for essential missions? And how can the DOD ensure the reprioritization of spectrum for defense use when there’s an urgent need?

Unique defense needs for DSS

DSS is in commercial use today, supporting the seamless operation of 4G LTE and 5G in the same spectrum. Defense-commercial DSS is more than that. Yes, 5G and 4G LTE (and even 3G) may operate in shared spectrum. What’s new is that defense use cases and applications demand rigorous levels of security, reliability, and performance that were not considered for the commercial world. And defense activity must not be compromised by unintended or unwanted interference.

For DSS to work for defense organizations, the DOD needs confidence that:

  • The wireless network is set up properly to support the demands of today’s defense operations. This includes emerging 5G use cases such as smart bases, large-scale augmented reality/virtual reality battlefield training, command and control communications across joint forces in the battlespace, and telemedicine for lifesaving surgery.

  • The network performs well under duress. Defense networks need to work in congested and contested environments. Rugged terrain, massive amounts of traffic, cyberattacks, jamming, and spoofing are all potential hazards that must be anticipated, accounted for, and reliably overcome for missions to succeed.

  • Communications and connections are not significantly degraded when the spectrum is shared. Though some interference or overlap may occur from commercial activity, that can’t get in the way of defense connections and communications getting through quickly and securely. Data and information need to be delivered and available right away. Verbal and visual communications must be received and understood. There’s no time or room for delays or degraded connections.

Defense organizations are actively researching and developing solutions to align commercial and military activity within shared spectrum. In collaboration with industry and academia, teams are working to ensure that spectrum is available and prioritized when and where it’s needed.

“We must figure out how to share this band if we are to unleash a new wave of network innovation and break the global dependency on compromised 5G networks sold by state-subsidized, antagonistic peer competitors,” said Deb Stanislawski, Director of the Office of the Undersecretary of Defense for Research and Engineering (OUSD(R&E)) 5G Tranche Prototyping and Experimentation in a December 2021 press release announcing the kick-off of 5G DSS experimentation at Hill Air Force Base.

The stakes are high. To realize the 5G advantage, the DOD must move quickly. Navigating the inevitability of DSS is essential to get it right – to ensure warfighters can reliably and securely connect and communicate in any spectrum band, in any environment.


Navigating the inevitability of DSS is essential... to ensure warfighters can reliably and securely connect and communicate in any spectrum band, in any environment.

Shaping requirements and supporting a transition to DSS

Defense requirements for 5G DSS are still in development. Testing and evaluation of emerging solutions and techniques can help to shape those requirements – and support the desired transition to defense-commercial DSS. Network digital twins are key to robust, effective testing.

Network digital twins such as Spirent's Digital Twin solutions provide an end-to-end 5G test network built upon network emulation, traffic generation simulation and test automation. Digital twins can support 5G (and 4G LTE and 3G) DSS testing and evaluation for:

  • Defense-commercial DSS requirements definition. The lab environment enables defense organizations to test any component – or any combination of network technologies, from the physical layer through application layers – without a capital investment. R&D teams can test across a wide band of spectrum for numerous use cases when defense is sharing spectrum or retrieving the ownership. Results from large-scale 5G, 4G, and 3G testing can inform decisions around DSS requirements, technology solutions, and best practices for achieving optimal use of shared spectrum.

  • 5G network and technology performance. Vendor-agnostic testing and evaluation of prototype solutions and techniques can reveal network behavior and data, video, and voice communication quality today. By artificially impairing the network with massive traffic, cyberattacks, outages, and other interference, digital twins help reveal performance under anticipated congested and contested conditions.

  • Transition to DSS adoption. Robust automation, such as what’s available with Spirent’s 5G Digital Twin solutions, not only supports repeated and complex testing scenarios when 5G technologies are being developed and prototyped, they can also continuously monitor and revalidate live networks, once deployed.

Digital Twin Framework for DSS

Partnering with defense organizations for DSS

For defense organizations to adopt DSS, they need instant visibility into who is using shared spectrum, an understanding of any overlap or interference and, most importantly, control mechanisms to reclaim access to spectrum if needed. It’s an exciting, innovative, and critical time in the journey to 5G adoption.

Our team is proud to be supporting the effort, bringing more than 25 years of expertise to the U.S. and allied government agencies, contractors and service providers who are crafting DSS and other 5G defense solutions. With unmatched experience guiding end-to-end testing of performance and quality of services, our defense experts know what it takes to design and execute testing and evaluation at every phase of the DSS process.

As the DOD moves from DSS prototypes to activation and operation, digital twins ensure that technologies function in the lab and, when ready, that they perform as needed when live. Spirent is an expert defense and wireless network partner to support next-gen testing, evaluation, and validation/revalidation of DSS. And our digital twin solutions support testing of 5G, 4G, and 3G, so defense leaders can ensure their range of modern and legacy technologies will perform as needed with the available spectrum.

Learn more about Spirent solutions for government.




Stephen Douglas
Stephen Douglas


Spirent is a global leader in automated test and assurance for the ICT industry and Stephen heads Spirents market strategy organization developing Spirents strategy, helping to define market positioning, future growth opportunities, and new innovative solutions. Stephen also leads Spirent’s strategic initiatives for 5G and future networks and represents Spirent on a number of Industry and Government advisory boards. With over 25 years’ experience in telecommunications Stephen has been at the cutting edge of next generation technologies and has worked across the industry with service providers, network equipment manufacturers and start-ups, helping them drive innovation and transformation.