Calculation Options

The calculation options are saved in the individual pl5 files, in each link design ld5 file and in the PL50.ini file as the defaults. Note that the first line in the options display states which of the above three options are being displayed in bold type. In addition, if a link design module is active, then the default calculation options menu in inhibited. Specific details on the calculation options displayed in this paragraph are given in the respective Technical Reference chapter.

Default Calculation Options

As the title implies, these are the default values which will be used in all new link designs. These options are saved in the PL50.ini file in the Windows program directory and are loaded when the program starts. Select the Configure - Options - Default calculation options menu on the network display menu bar

Pathloss Data File Calculation Options

Each link data file (pl5 file) contains the calculation options used in that file. In any of the link design modules, select the Configure - Options - Calculation options menu item. Many of these options can also be accessed by clicking a panel on the status bar.

Link Design Rules Calculation Options

Each Link Design Rules file (*.ld6)  contains the calculation rules for the design. Select the Calculation Options menu in the Link design rules dialog.

Application - Radio Type

Set the basic application type: Microwave, Adaptive Modulation or Land Mobile, design frequency and polarization. Set the calculation method for the selected application.

Multipath - K Fading Method

Select the basic multipath fade algorithm and the associated options. The obstruction fading method can be set directly in its data entry form in the Transmission Analysis module; however, the data source can only be set here.

In North America and Canada use the Public obstruction fading data. In all other areas, use the ITU-R P.453-7 Refractivity data.

The Enable Co-channel operation can also be set in its data entry form in the Transmission Analysis module.

Space Diversity Methods

Select the space diversity, quad diversity and angle diversity method. Set the maximum diversity improvement factor.

Rain Options

Select either the Crane or ITU-R P.530 rain algorithm and the specific attenuation regression coefficients.

For the Crane algorithm specify the Rain data source. All other options can be set in the rain data entry form in the Transmission Analysis module.

Miscellaneous Calculation Options

Select the method for determining the atmospheric data for Microwave and Adaptive modulation applications. For Land Mobile applications, the location value for the location variability calculation can be selected.

Clearance Criteria

Pathloss Diffraction Algorithm

Diffraction Parameters

These options can be accessed in the Diffraction module by clicking on the Frequency pane on the status bar.

Tree type

This option applies to single trees and ranges of trees, which have been manually entered on the profile. The basic tree types are: bare trees, full leaf trees, evergreen trees and rain forest. Each of these types are classed as either wet or dry foliage. Tree loss on a path profile is calculated as the smaller of the losses calculated as a knife edge and the loss calculated as a lateral wave along the tree tops. The lateral wave loss calculation depends on the type of tree and the wet or dry classification.

Clutter category

The clutter category selection only applies to clutter databases which contain the clutter heights but no description. In a description only clutter database, the actual clutter category is used. The Wet foliage - Dry foliage options applies to all clutter databases.