Search Results

The search returned 1,237 publication(s) on its.ntia.gov.

Robert T. Johnk et al., “Conducted and Radiated Emissions Measurements of an Ultrawideband Surveillance Radar,” Technical Report NTIA TR-13-491, November 2012

We provide detailed descriptions of recent measurements conducted by the National Telecommunications and Information Administration Institute for Telecommunication Sciences in Boulder, Colorado. ITS engineers performed a comprehensive series of both...

This report describes the methodology and results of an investigation into the source, mechanism, and solutions for radiofrequency (RF) interference to WSR-88D Next-Generation Weather Radars (NEXRADs). It shows that the interference source is nearby ...

Traditionally, audio quality and video quality are evaluated separately in subjective tests. Best practices within the quality assessment community were developed before many modern mobile audiovisual devices and services came into use, such as inter...

Cou-Way Wang and T. Keech, “Antenna Models for Electromagnetic Compatibility Analyses,” Technical Memorandum NTIA TM-13-489, October 2012

This memorandum contains two compilations of antenna parameters. The first one is the collection of rules, regulations, and recommendations regarding antennas that are published by authoritative institutions such as NTIAthe FCC, International Telecom...

Heather E. Ottke and Chriss A. Hammerschmidt, “Specialized Algorithms for Spectrum Surveys,” Conference Paper, August 2012

With increased demand in the radio spectrum, there have been multiple recent campaigns to quantify spectrum occupancy through measurements. These measurements can pose many challenges, one of which is created by impulsive noise. Below 500 MHz, impul...

Frank H. Sanders and Roger A. Dalke, “Relationships Between Measured Power and Measurement Bandwidth for Frequency-Modulated (Chirped) Pulses,” Technical Report NTIA TR-12-488, August 2012

Measured power levels for radio frequency (RF) pulses that are frequency modulated (chirped) vary as a function of the bandwidth in which the measurement is performed; if chirped pulses cause RF interference, the power levels of the pulses in victim...

J. Wayde Allen, “A 3-Axis Antenna Array for Polarimetric Spectrum Surveys,” Conference Paper, August 2012

Complete and accurate characterization of the radio environment is necessary for effective management of an increasingly congested radio spectrum. Unfortunately most antenna systems commonly used to perform spectrum surveys only respond strongly to s...

Mark A. McFarland and Robert T. Johnk, “Characterizing an S-band Marine Radar Receiver in the Presence of Interference,” Conference Paper, August 2012

Characterizing the effects that out-of-band interference has on the performance of an S-band marine radar receiver’s IF output normally requires non-linear network analysis. We have developed a non-linear network analyzer from commonly available labo...

Andrew A. Catellier, Margaret H. Pinson, William J. Ingram, and Arthur A. Webster, “Impact of Mobile Devices and Usage Location on Perceived Multimedia Quality,” Conference Paper, July 2012

We explore the quality impact when audiovisual content is delivered to different mobile devices. Subjects were shown the same sequences on five different mobile devices and a broadcast quality television. Factors influencing quality ratings include v...

When radiofrequency pulse envelopes are observed away from their fundamental frequency their shapes differ from those at their fundamental frequency. Off-fundamental pulse envelopes tend to exhibit spikes at their rising and falling edges with lower...

John E. Carroll, Geoffrey A. Sanders, Frank H. Sanders, and Robert L. Sole, “Case Study: Investigation of Interference into 5 GHz Weather Radars from Unlicensed National Information Infrastructure Devices, Part 3,” Technical Report NTIA TR-12-486, June 2012

In early 2009, the Federal Aviation Administration (FAA) became aware of interference to Terminal Doppler Weather Radars (TDWRs) that operate in the 5600–5650 MHz band and provide measurements of gust fronts, windshear, microbursts, and other weather...

“FY 2011 Technical Progress Report,” Technical Progress Report, May 2012

The Institute for Telecommunication Sciences (ITS) is the research and engineering laboratory of the National Telecommunications and Information Administration (NTIA) of the U.S. Department of Commerce (DOC). ITS provides technical support to NTIA in...

Michael G. Cotton et al., “ISART 2011: Proceedings of the 12th Annual International Symposium on Advanced Radio Technologies.,” Conference Proceedings NTIA SP-12-485, March 2012

These are the proceedings for the 2011 International Symposium on Advanced Radio Technologies hosted by the National Telecommunications and Information Administration’s Institute for Telecommunication Sciences in Boulder, Colorado. The conference fo...

This report describes one of three free-field radio frequency (RF) measurement systems that are currently being developed by engineers at the Institute for Telecommunication Sciences (NTIA/ITS). The objective is to provide estimates of the electrical...

Margaret H. Pinson, William J. Ingram, and Arthur A. Webster, “Audiovisual Quality Components: An Analysis,” Journal Article, November 2011

The perceived quality of an audiovisual sequence is heavily influenced by both the quality of the audio and the quality of the video. The question then arises as to the relative importance of each factor and whether a regression model predicting audi...

J. Wayde Allen, “A Prototype Antenna for Total RF Field Measurement,” Technical Report NTIA TR-12-483, October 2011

The total radio frequency (RF) field strength is the sum of all signals incident at a given location. These signals can originate from many directions and have various polarizations. This complicates the measurement of the total RF field since common...

Eric D. Nelson and Nicholas DeMinco, “Improved Estimation of the Third-Order Harmonic Emissions of Land Mobile Radio Base Stations,” Technical Report NTIA TR-11-481, September 2011

NTIA/ITS has developed an improved electromagnetic compatibility (EMC) analysis method that can be applied to more accurately model real scenarios for evaluating interference. The methodology described in this report can be used to conduct EMC analys...

Stephen Wolf and Margaret H. Pinson, “Video Quality Model for Variable Frame Delay (VQM_VFD),” Technical Memorandum NTIA TM-11-482, September 2011

Time varying delays of the output (or processed) video frames with respect to the input (i.e., the original or reference) video frames present significant challenges for Full Reference (FR) video quality measurement systems. Time alignment errors bet...

Robert J. Achatz, Roger A. Dalke, and John J. Lemmon, “In-Building Radio Enhancement Systems for Public Safety,” Technical Report NTIA TR-11-480, September 2011

Reliable public safety communications between system repeaters outside a building and portable radios inside a building is often not possible due to building attenuation. To circumvent this problem, increasing numbers of municipalities are requiring ...

Margaret H. Pinson and Stephen Wolf, “Batch Video Quality Metric (BVQM) User’s Manual,” Handbook NTIA HB-11-441d, September 2011

This handbook provides a user’s manual for the batch video quality metric (BVQM) tool. BVQM runs under the Windows XP® or Windows 7® operating systems. BVQM performs objective automated quality assessments of processed video clip batches (i.e., as o...