March 2021 | NTIA Technical Report TR-21-553
Eric D. Nelson; Duncan A. McGillivray
Abstract: This report describes the rationale, measurement methods, and analysis techniques for assessing Long Term Evolution (LTE) user equipment (UE) emissions in the Advanced Wireless Services - 1 (AWS-1) uplink band within the observable range of aeronautical mobile telemetry (AMT) installations at Edwards AFB (EAFB) and NASA Langley Research Center (NASA/LaRC). Site surveys and measurements were conducted to understand the AMT receiver systems’ radio frequency (RF) characteristics and survey the local spectrum environment’s UE activity through antenna azimuthal scans and test instrument bandwidths encompassing in-band and out-of-band emissions. Based on survey findings, select azimuths were revisited and numerous vector signal analyzer in-phase/quadrature (I/Q) captures of uncontrolled multiple UE over-the-air emissions were performed. A single controlled UE operating in a test mode facilitated captures for several data throughput rates of interest. Data post-processing techniques, analysis methods, and qualifying factors used to identify captures for inclusion in subsequent AMT receiver susceptibility bench top studies are detailed.
Keywords: vector signal analyzer; G/T; azimuthal scans; AWS-1; I/Q capture; spectrogram; uplink emissions; spectrum contours; stationarity analysis
For technical information concerning this report, contact:
Eric D. Nelson
Institute for Telecommunication Sciences
Disclaimer: Certain commercial equipment, components, and software may be identified in this report to specify adequately the technical aspects of the reported results. In no case does such identification imply recommendation or endorsement by the National Telecommunications and Information Administration, nor does it imply that the equipment or software identified is necessarily the best available for the particular application or uses.