Institute for Telecommunication Sciences

On Thursday, NTIA’s Institute for Telecommunication Sciences (ITS) released final test reports to commercial entities that participated in spectrum sharing testing on a model that would allow commercial and military use in the 3.5 GHz Citizens Broadband Radio Service (CBRS) band. The completed tests will drive progress toward initial commercial deployments in the band, prized for its excellent mix of capacity and coverage capabilities. With 4G LTE technology for the band available today, industry has already begun to develop specifications to support 5G deployments.

NTIA’s ITS oversaw rigorous testing, which included using a wide variety of scenarios and situations to test a Spectrum Access System’s (SAS) ability to manage CBRS devices while protecting incumbent federal and commercial operations in the 3.5 GHz band. The Federal Communications Commission anticipates relying on the test reports to certify that a SAS is complying with its rules.

Last year, ITS conducted the certification testing on Environmental Sensing Capability sensors for the CBRS band. The ESC sensors are intended to work with the SASs to enable dynamic sharing and were certified by the FCC in late April 2019. The completion of both the SAS and the ESC testing continues a 100-year tradition of ITS performing independent research and engineering in telecommunications to advance efficient spectrum use.

NTIA’s engineering lab has shared Spectrum Access System (SAS) laboratory test reports with the commercial entities that participated in spectrum sharing testing at the Institute for Telecommunication Sciences. The reports are a critical part of advancing the sharing model in the Citizens Broadband Radio Service 3.5 GHz band.

The reports include a comprehensive analysis and interpretation of the test results to ensure accuracy and consistency. This work adds to already substantial work in progress in developing the 3.5 GHz band, which is prime mid-band spectrum that offers a mix of capacity and coverage capabilities. The SAS manages the environment where potential commercial spectrum systems will operate. The Federal Communications Commission anticipates relying on the test reports in certifying that an SAS is in compliance with its rules.

The International Telecommunication Union (ITU) has adopted NTIA software as the global standard to optimize radiofrequency (RF) spectrum sharing between air and ground systems across a broad range of frequencies. The software was released earlier this month and is available on NTIA's Github page.

Software standards are a foundational tool for work to enable spectrum sharing, which is playing a key role in helping meet the demand for more airwave capacity as the U.S. advances development of 5G wireless networks and other emerging technologies. Scientists and engineers must be able to accurately calculate radio signal performance under various conditions, and from there build models to protect against interference when two users share the same spectrum.

The ITU’s Radiocommunication Sector (ITU-R) oversees global coordination and management of radio-frequency spectrum resource use. The ITU-R adopted NTIA’s P.528 reference software implementation, a method for computing propagation loss for air-to-ground signal paths in the frequency range from 125 MHz to 15,500 MHz.