COMPARISON OF PROPAGATION MEASUREMENTS WITH PREDICTED VALUES IN THE 20 TO 10,000 MHz RANGE

Longley, Anita G.; Reasoner, R. K.

doi:10.21236/ad0703579

Cited by 19 publications

(5 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Taking into account the probability of direct visibility between the source and observation point and using the corresponding formulas (11) and (19) we obtain for I co the following expression [34][35][36]:…”

Section: The Problem Of Single Scattering and Diffractionmentioning

confidence: 99%

“…Usually their estimations are fairly involved and aimed at calculating the loss of point-to-point paths. Later, during the seventies, vegetation and foliage losses have been reported [11][12][13] at frequencies up to 10 GHz but for relatively few paths. As follows from literature [14][15][16][17][18][19][20][21][22][23][24][25][26], trees have both absorbing effect (caused by scattering from foliage) and diffraction effect (caused by a lateral wave created by the top of the tree layer), mainly for propagation over the trees.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Radio Propagation in Rural Residential Areas with Vegetation

Blaunstein¹,

Censor²,

Katz³

et al. 2003

PIER

View full text Add to dashboard Cite

Abstract-In this paper we describe radio wave propagation within mixed residential area consisting of vegetation and houses. We assume no specific knowledge of the houses and vegetation location, but only of their statistical parameters. A three-dimensional (3D) stochastic approach, which is based on the statistical description of the terrain features, houses and vegetation, and deterministic description of signal decay is presented. The scattering and diffraction from trees and buildings, as well as the diffused reflection from the rough structures of the obstructions are modeled using the statistical description of an array of non-transparent phase screens randomly distributed on the rough terrain. The model, which accounts for single scattering and diffraction phenomena and a similar model, which accounts for multiple scattering effects without effects of diffraction are compared with measurements carried out in typical rural mixed residential areas with vegetation. The accuracy of the theoretical prediction is analyzed accounting possible variations of the terrain features. The approach presented here is applicable in many cases, where specific topographical information is not available.

show abstract

Section: The Problem Of Single Scattering and Diffractionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Radio Propagation in Rural Residential Areas with Vegetation

Blaunstein¹,

Censor²,

Katz³

et al. 2003

PIER

View full text Add to dashboard Cite

show abstract

“…Ten troposcatter links are selected from the "measured and predicted long-term distributions of tropospheric transmission loss" by the Office of Telecommunications Report OT/TRER 16 [12]. The RTBS_ERA5 model is compared with ITU-R P.617-2 and ITU-R P.617-5.…”

Section: A Rtbs_era5 Transmission Loss Validationmentioning

confidence: 99%

“…Many scholars have done extensive research in the estimate and forecast of transmission loss. The database of troposcatter links was developed in the mid-to-late-20th century through many troposcatter link experiments [11], [12]. Three scattering propagation mechanisms were proposed [8]: turbulent incoherent scattering, irregular-layer incoherent reflection, and steadylayer coherent reflection.…”

Section: Introductionmentioning

confidence: 99%

A New Model for Estimating Troposcatter Loss and Delays Based on Ray-Tracing and Beam Splitting With ERA5

Zhang

Chen

Liu

et al. 2022

IEEE Trans. Antennas Propagat.

View full text Add to dashboard Cite

The atmospheric environment is one of the critical factors affecting troposcatter transmission loss and propagation delay. This article proposes a new estimation model that can accurately calculate troposcatter transmission loss and propagation delay with a numerical weather model (NWM). The ERA5 reanalysis data as the NWM are applied to construct the new model. The 3-D ray-tracing and beam splitting are used to calculate propagation paths and delays. Compared with the existing methods, the new model thoroughly considered the bending and delaying effects of the atmospheric environment on electromagnetic waves, resulting in more accurate estimates. The transmission loss calculation capability of the new model is compared with the International Telecommunication Union (ITU) model and the terrestrial trans-horizon propagation loss data banks. The propagation delay calculation capability is compared with the Bello model. These comparison results show that the new model sufficiently reflects the meteorological environment's influence on transmission loss and propagation delay. Finally, the daily variation characteristics of losses and delays are analyzed using the new model and further validate the model performance.

show abstract

“…Usually their estimations are fairly involved and aimed at calculating the loss of point-to-point paths. Later, during the seventies, vegetation and foliage losses have been reported [Longley and Reasoner, 1970;Reudink and Wazowicz, 1973;Swarup and Tewari, 1979] at frequencies up to 3 GHz but for relatively few paths. As follows from literature [Tamir, 1967[Tamir, , 1977Sachs and Wyatt, 1968;Dence and Tamir, 1969;Vogel and Goldhirsch, 1986;Matzler, 1994;Lebherz et al, 1992;Weissberger, 1982, Hagn andBarker, 1970], trees have mostly absorbing and scattering effects for propagation inside the trees layer and lesser diffraction effects, mainly for the case of propagation over the trees.…”

Section: Introductionmentioning

confidence: 99%

Prediction of UHF path loss for forest environments

et al. 2003

View full text Add to dashboard Cite

[1] We describe radio wave propagation within terrain with vegetation, based on the measurements performed in a forested areas using low transmitter (TX) and receiver (RX) antenna elevations. We continue to investigate 3-D statistical multiparametric model of radio wave propagation above the rough terrain with some modifications made to describe multiple scattering of the signal field from randomly distributed trees, as phase screens, that model the random structure of trees with the rough surfaces and the irregular structure of branches and leaves, and other roughnesses placed on the ground surface. The scattering effects of trees and roughnesses are considered using a statistical description of an array of randomly distributed screens placed on a rough terrain. At the same time, an empirical short-range path loss model which is based on measurements carried out in typical forested areas in Denmark is considered. Comparison between results obtained from the statistical and the empirical models and those obtained from examination of the experimental data, as well as with the results of other existing models, is presented. It is shown that both models predict the exponential field intensity decay with the wide range of the power law index variations (from -2.5 to -4.3) with accuracy Ϯ6 dB with respect to experimental data and which is better than that obtained from other existing theoretical models.

show abstract

COMPARISON OF PROPAGATION MEASUREMENTS WITH PREDICTED VALUES IN THE 20 TO 10,000 MHz RANGE

Cited by 19 publications

References 2 publications

Radio Propagation in Rural Residential Areas with Vegetation

Radio Propagation in Rural Residential Areas with Vegetation

A New Model for Estimating Troposcatter Loss and Delays Based on Ray-Tracing and Beam Splitting With ERA5

Prediction of UHF path loss for forest environments

Contact Info

Product

Resources

About