(From Ian G3TVU Quick Start guide, january 2008)
There are a number of types of direct Radio Coverage plots, plus a 'Route Radio Coverage' feature, and two ways to 'Find Best Sites' for communication. This is where locations capable of providing Radio Coverage to a number of selected Units, or to all the Waypoints generated by the Object Editor on a Route, can be plotted.
In the following plots, the fixed unit(s) and mobile unit - whose parameters are to be used as the receiver - have to be selected. You also have to decide on the Units of measurement and range of signal levels to be displayed, plus the maximum Range to be plotted. It should be noted that the display generated for a Fixed Unit 'Gain' antenna is as if that antenna was pointed towards a particular azimuth - it can be set as a link direction or defined in degrees, i.e. its radiation pattern and direction does apply to the plot. The antenna pattern can be shown on the plot by checking 'Draw' which creates a small drawing of the antenna pattern overlaid at its location aligned with its azimuth. The Mobile Unit however is treated as if it has an 'Omni' antenna, even if in fact a gain antenna is specified in its System. The effect of this is to simulate a gain antenna at the mobile Unit which always points towards the Fixed Unit for every location.
With all these plots it is important to plot over a greyscale or black/white picture to avoid color degradation. An even better way is to produce a 'Blank' picture by merging an elevation map of an area with a road map after setting the merge screen to 'Copy' and contrast set to zero, with brightness set to 2.5. This will produce a white screen which can be saved as a new picture under the name 'Blank'. (Don't forget to 'reset' the brightness and contrast afterwards on the Merge pane, as you may think the servers are down!)
As an alternative method of producing the blank white screen which contains the elevation data, open a Map Picture and save it as the name 'Blank'. Next open 'Picture properties' - select 'Grey scaled slope', contrast to 0% and Brightness to 100%. A click on 'Draw' will then produce a white screen which can be saved again as 'Blank'. This procedure is used to avoid overwriting the original source picture properties.
The Blank screen (which holds the elevation data) can then be used to produce the color plots without any other detail, and saved as a new picture. These color pictures can then be merged over any other picture you have prepared to show pertinent detail.
Radio Coverage Plots can be performed in Single Polar or Combined Cartesian form. The working units displayed being selected from S-Unit, dBm, µV or dBµV/m over an automatic or defined range.
Single Polar plots are performed in a Radial manner, where plot areas may be defined for azimuth and radial range.
With Combined Cartesian plots, these are performed in an X-Y mode with a defined pixel resolution. There is also an option for selected rectangular area plots to be performed.
With Combined Cartesian Plots, the following functions are available:
- Finding sites in a network
- Finding sites using waypints
Finding sites in a network
Where it is required to locate a Control Unit, capable of communicating with a number of fixed subordinate Units within a network, at a suitable position on a map, the Find Best Sites function can be invoked.
The resultant plot displays areas where communication is achievable with a specified percentage of subordinate Units, allowing a choice of location to be made for the Control Unit with consideration to site accessibility.
Finding sites using waypoints.
Waypoints can be placed on a map using the Object Editor, and the Best Site for a Control Unit to communicate with them found.
Where it is required to locate a Control Unit, capable of communicating with a Mobile subordinate Unit as it traverses a Route, at a suitable accessible position on a map, the Find Best Sites function can be invoked, but using Waypoints.
The Waypoints are generated using the Object Editor, and this procedure is also suitable for Split Routes.
Route radio coverage
Using the Object Editor, Route lines can be drawn on the map using waypoints and saved for future use. The Route Radio Coverage feature is described, where the Radio Performance between:
a) a mobile Unit traversing the Route on the map in defined step increments, with
b) a specified fixed Unit,may be evaluated.
At any point on the Route, the Radio path profile and parameters can be examined in detail using the Radio Link pane.
A second ability of the Object Editor is to generate a sequence of unconnected Route segments on the map. This page describes how to use the Object Editor to generate segmented multiple Routes and evaluate the Radio Performance along a sequence of Split Routes.