Outputs circular sectors of influence for point features that have directions defined by azimuths (degrees clockwise from North).

This transformer creates a number of sectors for each set of point features (collectively called a site), depending on each point’s direction of influence. Each sector fans out from the center point (called site point) of the site it belongs to, and has a user-defined radius. Sectors generated for a site may overlap with sectors of other sites. If you want to avoid overlaps between different sites, use the VoronoiCellGenerator transformer instead.

Typical Uses

  • Generating sectors for cellular tower antennae coverage


In the telecommunications industry, directional antennas are used in conjunction with each other for better coverage and stronger signal reception. These antennas each cover a sector of a complete circle that an antenna tower covers, with some areas of overlap between each two sectors.

This transformer can be used to determine the “Nominal” (assuming a whole circle is covered and there are no overlaps between sectors in one site) coverage field of directional antennas and receivers.

Input points and their azimuth values are received:

A center point is created for each site:

Note: Please note that after this step, the locations of input points play no part in the generation of sectors, and the values that determine sectors are the input points’ azimuths and radii.

Note: In this diagram, azimuth lines are drawn from the center point for a better visual understanding of how this transformer computes sectors.

Polygon sectors are generated. The sector corresponding to each point will span an area determined by the radius set and

(The point's azimuth + adjacent azimuth (in degrees))/2

This means that each point's azimuth will be in the interior of its generated sector, and the boundary segment between sectors will bisect the angle between the two sector point's azimuth values. Resulting sectors will look like this:


Input Ports

Output Ports


Editing Transformer Parameters

Using a set of menu options, transformer parameters can be assigned by referencing other elements in the workspace. More advanced functions, such as an advanced editor and an arithmetic editor, are also available in some transformers. To access a menu of these options, click beside the applicable parameter. For more information, see Transformer Parameter Menu Options.

Defining Values

There are several ways to define a value for use in a Transformer. The simplest is to simply type in a value or string, which can include functions of various types such as attribute references, math and string functions, and workspace parameters. There are a number of tools and shortcuts that can assist in constructing values, generally available from the drop-down context menu adjacent to the value field.

Dialog Options - Tables

Transformers with table-style parameters have additional tools for populating and manipulating values.

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Keywords: "cellular phone" phone tower antenna coverage "cell phone" cel