Publications

This technical memorandum discusses simplified procedures for calculating near field and far field intensities of several types of aperture and wire antennas.

This report documents an analysis of the probability of interference from systems in the space services to aeronautical telemetry system using the 2200-2290 MHz band. These calculated results may be used to determine the coordination requirements for compatible operation between these systems, if a relaxation in the power flux density limits is adopted.

This technical memorandum provides additional guidance in applying procedures for finding the near field power density.  The technical memorandum also examines the feasibility of using simple models to calculate the off-axis near-field power density of wire and aperture antennas.

This report describes the use of space services by the U.S. Government in support of NTIA's Long Range Plan for Management and Use of the Radio Spectrum. The report addresses national and international regulations as well as frequency allocations, current and future government use of the space services, and spectrum management issues.

This study examined the sharing of spectrum between analog and digital land mobile radios in the 162-174 MHz band. Recommendations regarding cochannel and adjacent channel coordination distances have been adopted.

This report describes a new technique for calculating the spectrum space used by existing frequency assignments.  The Spectrum Use Model (SUM) determines the amount of spectrum used at a given location or the probability that a given location is unavailable for a new assignment.

This report describes analysis models and software packages developed for the assessment of single-entry and aggregate interference from terrestrial emitters into terrestrial or airborne victim receivers. The menu-drive computer programs provide user options for input/output computations, parametric representations, propagations models and emitter distributions. The flexibility in the scenario creation, parameter selection, and computation mode, renders the models applicable to a wide variety of EMC assessments and conditions. Model descriptions, technical formulations, user manuals, and sample runs are provided in this report.

The technical and operating characteristics of meteor burst systems of importance for spectrum management applications are identified. A technical assessment is included which identifies the most appropriate frequency sub-bands within the VHF spectrum to support meteor burst systems. The electromagnetic compatibility of meteor burst systems with other equipment in the VHF spectrum is determined using computerized analysis methods for both ionospheric and groundwave propagation modes. It is shown that meteor burst equipment can cause and are susceptible to groundwave interference from other VHF equipment. The report includes tables of geographical distance separations between meteor burst and other VHF equipment which satisfy interference threshold criteria.

This handbook is intended to provide estimates of radio wave propagation loss between transmitting and receiving antennas of various heights and transmission frequencies above the assumed smooth-earth surface calculated using the NLAMBDA computer model. For many cases involving electromagnetic compatibility analysis, the curves of predicted transmission losses in this report may be used to estimate the transmission losses of the desired and undesired signals. These estimated loss values are given in dB as BASIC MEDIAN TRANSMISSION LOSS for antennas with effective heights up to 5000 meters, operating in the 100-20,000 MHz frequency range, over land or sea, at great circle earth surface distances up to 1000 kilometers.