Understanding mountain radio signal paths mendo radio. Software tools for the planning of vhf, uhf and microwave systems. Vhf and uhf are not thought to be bands where propagation affects your signal, but there are times when your signal will propagate well beyond their normal limits. Radio mobile software by roger ve2dbe welcome to the. The author is senior engineer at cavell, mertz and associates inc. Aug 31, 2017 the author is senior engineer at cavell, mertz and associates inc. A free online vhf uhf propagation tool for technical and nontechnical users charles w. Radio signals are affected by terrain elevation between the sites, and obstructions, including trees, buildings, etc. Dec 11, 2011 vhfuhf radio propagation in mountainous terrain can be difficult and sometimes may seem impossible. Propagation software tools are an essential part of the planning capability of the. A free online vhfuhf propagation tool for technical and nontechnical users charles w. Free online vhfuhf propagation tool for technical and non. Radio mobile rf propagation simulation software radio. It uses digital terrain information and a mathematical model to simulate radio transmissions between two fixed sites radio link or between.
Software based dmc generation for uhf wireless radio propagation. It uses data gathered by automatic packet reporting systeminternet service aprsis from packet stations in the amateur radio service. Create terrain profiles using digital elevation models. The longleyrice irregular terrain model was originally developed in the late 1960s. Irregular terrain model itm longley rice 20 mhz 20 ghz abstract. Feb 25, 2015 qradiopredict is an experimental software for vhf uhf propagation prediction and radio coverage analysis. Radio propagation radio propagation is the study of how radio waves travel from a transmitter site to a receiver site through the atmosphere. Can we accurately predict terrain effects on radio waves. Kingston amateur radio club propagation prediction. Imagine a large wave hitting a rock as opposed to a. Radio mobile online online rf propagation simulation. This service offers a variety of propagation models for different purposes.
Tap is comprised of individually licensed software modules, which may be purchased in almost any combination depending on user requirements for area coverage studies, path profiles, interference studies, presentation of results, and budget. Calculations radio mobile rf propagation simulation software. Propagation prediction software asaps advanced stand alone prediction system the ips advanced stand alone prediction system asaps allows the prediction of sky wave communication conditions in the hf high frequency and low vhf very high frequency radio spectrum or short wave band 1 to 45 mhz. The radio coverage tool is based on the longleyrice vhfuhf its model2, and includes a nearly 1 terabyte digitized worldwide terrain database, based. Printable copies of these propagation curves are available at fm and tv propagation curves graphs. Rf signal propagation, loss and terrain analysis tool. Tap software softwright, llc terrain analysis package. A terrestrial rf path analysis application for linuxunix. Sep 05, 20 softwrights terrain analysis package tap is used by federal agencies, statelocal public safety departments, energy companies, utilities, and consultants to evaluate radio transmitter sites. A free online vhfuhf propagation tool for technical and non. Propagation below 1 mhz is very insensitive to the value of k. Vhf propagation map this map shows realtime radio propagation from stations operated near 144 mhz. Vhf and uhf can be affected by the following conditions, though. Tap rf radio microwave design, analysis, and planning software.
Dec 06, 2017 when operating a radio in the field, getting the best out of your equipment relies on understanding what is the best communications device to use in a given situation. High frequency hf propagation models 230 mhz irregular terrain model itm longleyrice 20 mhz 20 ghz if77 wave propagation model gierhartjohnson airground millimeterwave propagation model mpm 1 ghz 1 thz terrain data and extraction routines. While hf propagation pundits are concerned with the ionosphere, vhfuhf enthusiasts generally have their sights set a little lower on the troposphere. A abstract this paper presents and compares measured propagation data taken at four unlicensedband frequencies. In the program all functions of radio mobile are described. The program is organized into eight path design modules, an area signal coverage module and a network module which integrates the radio paths and area coverage analysis. Qradiopredict radio propagation prediction and simulation tool for vhfuhf, based on the irregular terrain model, also known as longleyrice. As of this moment, only terrain following movement is possible in this mode. It is not essential for the program user to know r and k of the ground select the type of terrain from the list which best fits the average of the different types which may exist along a particular path. Softwrights terrain analysis package tap is used by federal agencies, statelocal public safety departments, energy companies, utilities, and consultants to evaluate radio transmitter sites.
This algorithm became the basis for the governments irregular terrain model itm software, which, in turn, was adopted by the fcc as the approved method for computing service contours and interference between fixed stations. Qradiopredict is an experimental software for vhfuhf propagation prediction and. Foliage and urban loss over flat or rugged terrain can be calculated on. Fm, tv, vhf high low, uhf, 700800900, cellular, microwave. A free online vhfuhf propagation tool for technical and. I worked some eme earthmoonearth, or moon bounce during those days back in the 70s and early 80s.
Under normal or flat conditions most vhf and uhf communications are generally thought to be line of sight. High frequency hf and very high frequency vhf transmissions are an important part of tactical operations, especially in rough terrain or remote locations. Nautel limited hacketts cove, ns canada abstract broadcasters are often confronted with questions about fm, tv and stl propagation, such as is it more effective to raise my antenna 100ft, or increase the. As you know, higher frequencies travel primarily lineofsight. The most important propagation mechanism for shortrange communication on the vhf and uhf bands is that which occurs in an open field, where the received signal is a vector sum of a direct lineofsight signal and a signal from the same source that is reflected off the earth. Vhfuhf openings happen sporatically and you cannot predict them as well as hf propagation. Vhf uhf radio propagation coverage tool slideshare. Vhfuhf propagation planning for amateur radio repeaters.
This means that since the waves are longer with vhf, its harder to disrupt the wave, therefore it travels further. In this paper, the effects of terrain on electromagnetic wave propagation in the vhf band was investigated using two transmitters both operating in the vhf frequencies. Institute for telecommunication sciences resources radio propagation software itm itm. This software by roger coude ve2dbe predicts the performance of vhf and uhf radio systems. It can be further enhanced with the addition of knife edge diffraction which will factor in terrain obstacles and antenna heights. Tactical hf vs vhf radio when should i use them barrett. This is a list of my vhfuhf century club program vucc totals. It uses digital terrain information and a mathematical model to simulate radio transmissions between two fixed sites radio link or between a fixed site and a mobile radio coverage.
Free online vhfuhf propagation tool for technical and nontechnical users. Feedback from radio professionals and developers is encouraged to optimise the models where possible. The class of an fm station may be retrieved from the fm query. Tap is comprised of individually licensed software modules, which may be.
Compared to uhfs range, which is 300 mhz to 3000 mhz, its clear that vhf has sometimes 10 times longer wavelengths. Elevation profiles are taken from nasa 1 degree srtm 3 arcsec. Pdf software based dmc generation for uhf wireless radio. Fundamentals of vhf and uhf propagation propagation over irregular terrain propagation in. Radio propagation prediction software an overview, article, tutorial about the basics of radio propagation prediction software for use on the hf bands for predicting broadcast coverage, as well as the possibility of establishing two way radio communications, maritime mobile radio communications, and for many more applications. Radio propagation is the behavior of radio waves as they travel, or are propagated, from one point to another, or into various parts of the atmosphere. Qradiopredict is an experimental software for vhfuhf propagation prediction. Oct 08, 20 this free online vhf uhf propagation tool can help you because it. Rf signal propagation, loss, and terrain analysis tool. Understanding the effects of varying conditions on. The pathloss program is a comprehensive path design tool for radio links operating in the frequency range from 30 mhz to 100 ghz. Qradiopredict is an experimental software for vhfuhf propagation prediction and radio coverage analysis.
The radio coverage tool is based on the longleyrice vhfuhf its model2, and includes a nearly 1 terabyte digitized worldwide terrain database, based on nasa shuttle radar terrain mapping data as well as other sources. The spring 2002 issue of cq vhf magazine carried an article entitled, a computerized analysis of vhf andabove, freespace radiowave propagation authored by splat. Softwright releases terrain analysis package tap 7. When operating a radio in the field, getting the best out of your equipment relies on understanding what is the best communications device to use in a given situation. The slice is a set of step distances from the center the chosen location together with the height of terrain at each step. Jan 20, 2020 radio propagation radio propagation is the study of how radio waves travel from a transmitter site to a receiver site through the atmosphere. I have always had an interest in the vhfuhf weak signal segment of our ham radio hobby. Qradiopredict is an experimental software for vhf uhf propagation prediction and radio coverage analysis.
Fundamentals of vhf and uhf propagation propagation over irregular terrain propagation in builtup areas area coverage and. As a form of electromagnetic radiation, like light waves, radio waves are affected by the phenomena of reflection, refraction, diffraction, absorption, polarization, and scattering. Resources listed under rf coverage category belongs to software main collection, and get. This free online vhf uhf propagation tool can help you because it.
Vhfuhf propagation radio society of great britain main. Unlike hf, they do not reflect off the ionosphere, so their range can be rather limited although knowledgeable dxers know special tricks, like meteor scatter. Tap comprises 27 different software modules, which may be purchased in various. Free space propagation is an unhindered mode that is not influenced by the presence of any behaviormodifying object like the earth, atmospheric refraction, etc. Radio mobile online is a radio wave propagation prediction tool dedicated to amateur radio. Vhfuhf propagation planning for amateur radio repeaters steve stearns, k6oik. When we say propagation software, we refer to models that run pathloss signal propagation studies, as distinguished from the software platform that manages the process and plots the results geographically over a map. Propagation comparisons at vhf and uhf frequencies xiaohu zhang, student member, ieee, thomas weston burress, keith b.
Fm and tv propagation curves federal communications. Back in my younger days i worked a lot of 50 mhz, 144 mhz, 220 mhz, and 432 mhz. The areas noted in the forecast have the necessary atmospheric conditions to produce tropospheric bending of vhf, uhf andor microwave radio waves. Uses openstreetmap tiles or public sattelite imagery as background. Kuhn, senior member, ieee kansas state university, manhattan, ks, 66502, u. Okumura wellknown propagation model for vhf and uhf land mobile. Currently it works on linux and windows 32 bit vista tested. Radio propagation prediction software electronics notes.
The digital terrain information comprises three databases. Vhfuhf radio propagation in mountainous terrain can be difficult and sometimes may seem impossible. Hf terrain analysis hfta is a powerful but easy to use tool but requires a set of data files which describe a series of 2d slices of terrain around a chosen location. Other frequencys are used for broadcast of radio and tv vhf and uhf, 50800. Geotiff load your own geotiff files shapefiles many vector and point files by default or load your own population layer census 2000 and 2010 supported bands. Radio mobile is propagation simulation software free to the amateurradio community. Radio mobile is a advanced pice of software and has features that can be of interest for advanced users. Radiolink propagation prediction calculate path losses of a pointtopoint radio link. Radio mobile updated radiomobile is an excellent and very detailed radio path mapping software, vhf uhf propagation predictor. Radio mobile rf propagation simulation software the. Pathloss microwave radio link design and planning software. Terrain layer 3 90 meter resolution standard, 1 30 meter resolution available on demand.
Analysis of vhfandabove, freespace radiowave propagation authored by splat. Use it to design networks, validate existing coverage and publish network maps. Under normal or flat conditions most vhf and uhf communications are generally thought to be line of sight the higher your antennas the better. Radio propagation prediction, radio coverage analysis and. Antenna height above average terrain haat values for a particular fm or tv station can be obtained from the fm query or the tv query, or use the haat calculator. The spring 2002 issue of cq vhf magazine carried an article entitled, a computerized analysis of vhfandabove, freespace radiowave propagation authored by splat. This windows free software is a tool used to predict the performance of a radio system.
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