VHF Troposcatter Propagation VHF 102 KK 6 MC

What is Troposcatter? Scattering (not reflection) from inhomogenities (blobs of uneven density) in the

Troposphere is atmosphere from ground level to about 35, 000 feet. It is the

Useful References Dishman, QST, November 1961 SPLAT! < http: //www. qsl. net/kd 2

Troposcatter from Inhomengenities 51 st Central States VHF Society Conference. July 27 -30, 2017

Density Inhomogeneities (Blobs) in Upper Atmosphere 51 st Central States VHF Society Conference. July

Troposcatter Path Loss from Dishman QST, November 1961 51 st Central States VHF Society

Two Meter Path Loss as a Function of Distance 51 st Central States VHF

Loss very dependent on takeoff angle – Hills are nice 51 st Central States

Relative path loss increases as frequency increases – offset by increase in antenna capture

QSB is significant on Troposcatter 51 st Central States VHF Society Conference. July 27

Tools to Calculate Path Loss There is no first principles theory, all calculations are

Calculating Path Loss Capability with SPLAT! 51 st Central States VHF Society Conference. July

Radio Mobile On-line Calculations 51 st Central States VHF Society Conference. July 27 -30,

Using Radio Mobile Online Demonstration 51 st Central States VHF Society Conference. July 27

Create account or log in 51 st Central States VHF Society Conference. July 27

Initial Menu 51 st Central States VHF Society Conference. July 27 -30, 2017 |

Settings 51 st Central States VHF Society Conference. July 27 -30, 2017 | Albuquerque,

New Site 51 st Central States VHF Society Conference. July 27 -30, 2017 |

Submit 51 st Central States VHF Society Conference. July 27 -30, 2017 | Albuquerque,

New Link 51 st Central States VHF Society Conference. July 27 -30, 2017 |

You also get a map 51 st Central States VHF Society Conference. July 27

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VHF Troposcatter Propagation - VHF 102 KK 6 MC James Duffey NM VHF Society VHF 51 st Central States VHF Society Conference. July 27 -30, 2017 | Albuquerque, New Mexico 1

What is Troposcatter? Scattering (not reflection) from inhomogenities (blobs of uneven density) in the troposphere Allows propagation beyond normal line-of-sight and diffraction distances Aways present, although strength varies considerably 13 to 15 d. B Varies with time of day, season of year, weather Very dependent on effective radiated power, angle of radiation Viable propagation mode from 50 MHz (6 M) to over 10 GHz (3 cm) 51 st Central States VHF Society Conference. July 27 -30, 2017 | Albuquerque, New Mexico

Troposphere is atmosphere from ground level to about 35, 000 feet. It is the region where clouds are formed. 51 st Central States VHF Society Conference. July 27 -30, 2017 | Albuquerque, New Mexico

Useful References Dishman, QST, November 1961 SPLAT! < http: //www. qsl. net/kd 2 bd/splat. html > On line at: < http: //splat. adis. ca > Radio. Mobile < http: //www. cplus. org/rmw/english 1. html > < Atkins 51 st Central States VHF Society Conference. July 27 -30, 2017 | Albuquerque, New Mexico http: //www. bobatkins. com/radio/troposcatter. ht ml>

Troposcatter from Inhomengenities 51 st Central States VHF Society Conference. July 27 -30, 2017 | Albuquerque, New Mexico

Density Inhomogeneities (Blobs) in Upper Atmosphere 51 st Central States VHF Society Conference. July 27 -30, 2017 | Albuquerque, New Mexico

Troposcatter Path Loss from Dishman QST, November 1961 51 st Central States VHF Society Conference. July 27 -30, 2017 | Albuquerque, New Mexico

Two Meter Path Loss as a Function of Distance 51 st Central States VHF Society Conference. July 27 -30, 2017 | Albuquerque, New Mexico

Loss very dependent on takeoff angle – Hills are nice 51 st Central States VHF Society Conference. July 27 -30, 2017 | Albuquerque, New Mexico

Relative path loss increases as frequency increases – offset by increase in antenna capture area 51 st Central States VHF Society Conference. July 27 -30, 2017 | Albuquerque, New Mexico

QSB is significant on Troposcatter 51 st Central States VHF Society Conference. July 27 -30, 2017 | Albuquerque, New Mexico

Tools to Calculate Path Loss There is no first principles theory, all calculations are made with numerical constructs built to match observed data can be big variation in results depending on whose technique you use Calculations can be made by hand using troposcatter loss formulas – requires knowing distance to nearest obstruction on each end. Central States VHF Society 51 Visual Basic < Conference. July 27 -30, 2017 | Albuquerque, New Mexico st http: //www. bobatkins. com/radio/scatter 2. html > Computer tools using Longley-Rice NBS

Calculating Path Loss Capability with SPLAT! 51 st Central States VHF Society Conference. July 27 -30, 2017 | Albuquerque, New Mexico

Radio Mobile On-line Calculations 51 st Central States VHF Society Conference. July 27 -30, 2017 | Albuquerque, New Mexico

Using Radio Mobile Online Demonstration 51 st Central States VHF Society Conference. July 27 -30, 2017 | Albuquerque, New Mexico

Create account or log in 51 st Central States VHF Society Conference. July 27 -30, 2017 | Albuquerque, New Mexico

Initial Menu 51 st Central States VHF Society Conference. July 27 -30, 2017 | Albuquerque, New Mexico

Settings 51 st Central States VHF Society Conference. July 27 -30, 2017 | Albuquerque, New Mexico

New Site 51 st Central States VHF Society Conference. July 27 -30, 2017 | Albuquerque, New Mexico

Submit 51 st Central States VHF Society Conference. July 27 -30, 2017 | Albuquerque, New Mexico

New Link 51 st Central States VHF Society Conference. July 27 -30, 2017 | Albuquerque, New Mexico

Submit 51 st Central States VHF Society Conference. July 27 -30, 2017 | Albuquerque, New Mexico

You also get a map 51 st Central States VHF Society Conference. July 27 -30, 2017 | Albuquerque, New Mexico