CLI Reference Guide

130 CHAPTER 4: PLANNING THE 3COM MOBILITY SYSTEM
Specifying the RF
Characteristics of a
Floor
3WXM uses RF attenuation information in the floor plan when
calculating how many MAPs you need and where to place them to
provide the wireless coverage required for the floor. The RF attenuation
information comes from the attenuation values associated with objects
on the floor plan that have been converted into RF obstacles. An RF
obstacle is an object that has an attenuation value associated with it.
You can add RF obstacles to a floor plan in the following ways:
 Select the objects that will be RF obstacles and assign attenuation
values to them. This method is available for floor plans that are
imported from CAD drawings. (See “Converting Objects into RF
Obstacles” on page 130.)
 Use the graphics tools in the Insert RF Obstacle group box of the Edit
Content page to draw the RF obstacles and assign attenuation values
to them. This method is available for any floor plan. (See “Drawing RF
Obstacles” on page 133.)
Recommendations Consider the following when creating RF obstacles:
 Be aware if a CAD drawing contains overlapping objects. If you create
RF obstacles on objects that are on top of each other, the attenuation
is increased at that point. (3WXM sums the attenuation factors in dB.)
 Grouping objects is useful if you want one attenuation factor for an
area on the floor.
Converting Objects
into RF Obstacles
You have several options when creating RF obstacles:
 Convert all objects in a layer of a CAD drawing into RF obstacles.
 Convert all objects in an area of the drawing into RF obstacles.
 Convert multiple objects in the drawing into RF obstacles.
 Convert grouped objects in the drawing into RF obstacles.
To create RF obstacles for all objects in a layer
3WXM preserves the layers defined in a CAD drawing. You can convert
all of the objects in the layer into a specific type of RF obstacle.
1 In the Layer Name column in the Edit Content page (in the Building
wizard), right-click the layer row in the table.
2 Select Create RF Obstacles. The Create RF Obstacle dialog box appears.