Spectrum Engineering
NOTE: These reports are available either on-line in PDF (portable document) format or only as hard-copy. If you would like a copy of a report that is not available electronically, please make note of the document number and submit your request to:
NTIA Office of Spectrum Management
System Engineering and Analysis Division
Tel. (202) 482-2608
Fax (202) 482-4595
e-mail edrocella@ntia.doc.gov
Related content
Championing the Nation’s Spectrum Engineers: NTIA and ITS Celebrate Engineers Week
Today marks the beginning of Engineers Week, a very special week recognizing NTIA’s critical national resource: Spectrum Engineers. Across our workforce in DC and our Institute for Telecommunication Sciences (ITS) lab in Boulder, CO, 62 talented and dedicated engineers propel our vital mission forward. ITS is NTIA’s research and engineering laboratory. The engineers that work at ITS apply their expertise so that the U.S. can realize the full potential of telecom and drive a new era of innovation, development, and productivity. Alongside their colleagues in our Office of Spectrum Management, ITS engineers are at the forefront of spectrum research and help lead America’s race to deploy 5G technologies and beyond.
As an engineer myself, I am honored to be the first female director in ITS’ 100 year history. Engineers Week is a 70 year old tradition to foster participation in engineering careers. I believe deeply in the power that STEM careers and education can have on individuals and society, and we at ITS and NTIA remain committed to help ensure that those opportunities are available to anyone with the drive and talent necessary. Regardless of background, each of our engineers is focused on one mission: ADVANCE innovation in communications technologies, INFORM spectrum and communications policy for the benefit of all stakeholders, and INVESTIGATE our Nation’s most pressing telecommunications challenges through research that employees are proud to deliver.
NTIA Report: Incumbent Informing Capability (IIC) for Time-Based Spectrum Sharing
The IIC is a mechanism for more reliably informing “new entrants” in a shared spectrum band when incumbent federal systems are operating in close proximity and thus need to be protected. New entrant access to the spectrum would be controlled through an enhanced, near-real-time Spectrum Coordination System (SCS). The IIC could replace extra layers of sharing techniques such as the environmental sensing capability (ESC), which presently is required by the Federal Communications Commission (FCC) for the Citizen Broadband Radio Service (CBRS) in the 3550-3700 MHz band.
Emission Spectrum Measurements of a 3.5 GHz LTE Hotspot
In response to proposals to introduce new Long Term Evolution (LTE) radio systems into the 3550–3650 MHz (called 3.5 GHz) portion of radio spectrum in the United States, a joint team of National Telecommunications and Information Administration (NTIA) and U.S. Navy electronics engineers performed emission spectrum measurements on a 3.5 GHz (LTE Band 42) wireless access point (WAP), or hotspot. The hotspot was packaged for indoor use but similar systems could be deployed outdoors. The authors measured the hotspot emission spectrum with 110 dB of dynamic range across 1.5 GHz of spectrum (from 2.7 to 4.2 GHz). Other data outputs include: spectra measured with the device tuned to its lowest, highest, and middle available operational frequencies; comparative peak-to-average spectra; and spectra measured when the hotspot was operated with 10, 15, and 50 resource blocks. The emission spectrum is plotted against proposed in band, out-of-band (OOB) and spurious emission limits; the spectrum meets those limits by at least 10 dB at all points. The results presented here may be used in electromagnetic compatibility analyses for future 3.5 GHz spectrum sharing between LTE-based transmitters and incumbent systems such as radar receivers.
Keywords: radar; electromagnetic compatibility (EMC); band sharing; spectrum sharing; out-of-band (OOB) emissions; spectrum measurement; Long Term Evolution (LTE); 3.5 GHz band; LTE band 42; emission limits; resource blocks; spurious emissions; wireless access point (WAP); wireless local area network (WLAN)