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Interfering link dialog windows

This set of dialog windows is aimed to update the parameters of interfering link in a scenario, create new interfering links or delete existing ones.

A given simulation workspace must contain at least one interfering link. Each Interfering link will be defined by two elements: an Interfering transmitter (IT) and Wanted Receiver (WR). A newly created interfering link is automatically initialised with the default parameters of first transmitter and receiver available in the SEAMCAT library.

To edit the interfering link of the current workspace select the Interfering Links command in the Workspace menu. This activates the Interfering links list window:

Select a link reference in the displayed list and click on Edit to modify the selected interfering link or click on Add to create a new interfering link. This activates the Interfering Link window where user can set/modify all scenarion parameters of given interfering link.

General

OBS: If the Interferring Link is a CDMA system, set the operating frequency of interfering link and check the box 'Interferer is a CDMA system' , this will activate a separte set of tabs to define the parameters of CDMA system.

The rest of this page deals with settings for Interfering links of non-CDMA systems. The General tabsheet gathers basic information required for definition of an interfering link:

• Identification
  • Reference (Name)
  • Description
• Definition:
  • Reference of the IT is selected by means of the Interfering transmitter combo box. This parameter is set by default (when the workspace is created) to the reference of the first available transmitter of the library. Note: Any change of the reference of the IT through this combo box automatically triggers the update of the associated parameters of the IT in this interfering link;
  • Reference of the WR is selected by means of the Wanted receiver combo box. This parameter is set by default (when the workspace is created) to the reference of the first available receiver of the library. Note: Any change of the reference of the WR through this combo box automatically triggers the update of the associated parameters of WR in this interfering link.
  • Frequency distribution (MHz) of the interfering transmitter, may be set constant or random.

Interfering transmitter (IT)

The Interfering transmitter tabsheet allows to edit parameters defining the IT.

General

The General sub-sheet contains following information:

• Identification:
  • Name and Description (freely editable fields)
• Emission characteristics:
  • Transmitter power of IT (dBm) - may be set constant or random,
  • Unwanted emissions mask (MHz/dBc/kHz) - see separate page on how to enter emission mask,
  • Unwanted emissions noise floor - checkbox and option of entering noise floor emissions,
  • Power control mechanism - selection of the checkbox if power control is activated.
• Power control parameters (data fields activated if power control mechanism selected):
  • Power control step size (dB),
  • Minimum threshold of PC mechanism (dBm at wanted receiver),
  • Dynamic range of PC mechanism (dB),
• IT antenna height and pointing parameters:
  • Antenna height (m),
  • Antenna azimuth (deg),
  • Antenna elevation (deg).

Antenna

The Antenna sub-sheet contains all information needed to describe the type of IT antenna:

• Antenna reference name (freely editable),
• Antenna description (freely editable),
• Antenna gain (dBi) and radiation patterns.

Wanted receiver (WR)

The Wanted receiver tabsheet allows to edit parameters defining the WR.

General

The General sub-sheet contains following information:

• Identification:
  • Name and Description (freely editable fields)
• WR antenna height and pointing parameters:
  • Antenna height (m);
  • Antenna azimuth (deg);
  • Antenna elevation (deg).
• WR Sensitivity (dBm).

Antenna

Antenna sub-sheet contains all information needed to describe the type of WR antenna:

• Antenna reference name (freely editable),
• Antenna description (freely editable),
• Antenna gain (dBi) and radiation patterns.

IT-WR path

The IT-WR path tabsheet gathers information needed to define the modeling of the path between IT and WR:

• relative mutual location of the IT and WR,
• propagation loss on the IT-WR path (important when applying power control).

Relative location

The Relative location sub-sheet allows user to define information required for calculation of mutual positioning of IT and WR.

Two modes to define relative location are available:

• If correlated distance option is selected, this means that WR is positioned at a fixed location with regard to IT, and their mutual placement is defined via dX/dY parameters (with IT being the reference point),
• When Correlated distance is unchecked, it means that WR is randomly placed around IT and the two parameters define the range of this random positioning:
  • Path azimuth (deg) - describes the azimuthal direction of possible WR locations as seen from IT. (Please read here about path azimuth settings);
  • Path distance factor (times) - describes the extent of possible WR locations in terms of distance from IT. Note: This field describes only the random factor, whereas the actual distance will be obtained during calculations by multiplying the trialled factor value with the coverage radius value, defined in the next field on this dialog window. Please read here about the suitable choice of distribution function for azimuth/distance factor.

Coverage radius field gives user possibility to define the maximum range of WR-IT placement when they are placed in non-correlated fashion:

• User-defined radius option allows user to enter the maximum radius directly below;
• Noise-limited network option will calculate the coverage radius at the beginning of EGE cycle, based on formula for noise-limited network. If this option is chosen, a set of input boxes will appear below allowing user to enter specific parameters required for this calculation;
• Traffic-limited network option will calculate the coverage radius at the beginning of EGE cycle, based on formula for traffic-limited network. If this option is chosen, a set of input boxes will appear below allowing user to enter specific parameters required for this calculation.

Propagation model

The Propagation model sub-sheet allows user to choose the suitable propagation model to be applied when calculating signal loss along the WR-IT path (important when applying power control at IT). Please see the separate information pages regarding the choice and settings of the propagation models.

Interfering transmitter - Victim Receiver (IT-VR) path

The IT-VR path tabsheet is used to define information related to modeling of the interference link, i.e. the path between IT and VR:

• relative mutual placement of IT with respect to VR,
• propagation loss on the path between the IT and the VR.

Relative location

The Relative location sub-sheet contains the information required to define the mutual positioning of the IT and VR. The following definition modes are available for both uncorrelated and correlated cased:

Uncorrelated cases

• None : each interfering signal calculation results from the contribution of n_active interering transmitters located in a circular area the radius of which (called simulation radius) is defined by the user. The random placement of ITs in this area isdetermined by azimuth and distance factor distributions entered by the user. In this mode, required parameters are:
  • distance factor distribution of the IT with regards to the VR,
  • azimuth distribution of the IT placement with regards to the VR position,
  • simulation radius,
  • n^active : number of active interfering transmitters in the simulation;
• Uniform density : each interfering signal calculation results from the contribution of n^active interering transmitters uniformly located in a circular area, the radius of which (called simulation radius) is automatically derived from the density and activity of transmitters entered by the user. In this mode, required parameters are:
  • azimuth distribution of the IT placement with regards to the VR position,
  • n^active : number of active interferers in the simulation,
  • dens_it: density of interfering transmitters,
  • P_it : probability of transmission,
  • activity_it(time) : a kind of look-up table, which describes a temporal activity variation as a function of the time of the day (e.g. for various hours of the day). The time value used for looking up a particular activity value for a given simulation is fixed for a given simulation by parameter time,
  • time : hour, the entered value have to correspond to defined range of activity_it(time) function,
  • Protection distance - the minimum distance between IT and VR;

• Closest : each interfering signal calculation results from the contribution of just one interfering transmitter. This IT is randomly placed in a circular area, the radius of which (called simulation radius) is automatically derived from the density and activity of transmitters entered by the user. In this mode, required parameters are the same as described above for the Uniform density mode, except that user can not set multiple number of ITs;

Note: For further information about the calculations based on the density parameters, refer to section on  relative location of IT and VR.

Correlated cases

• it/vr : fixed placement of IT with respect to VR,
• it/wt : fixed placement of IT with respect to WT,
• wr/vr : fixed placement of WR with respect to VR,
• wr/wt : fixed placement of WR with respect to WT.

In these four cases of fixed placement relative location of the two involved transceivers is described by dX/dY displacement, with origin being on the respective transceiver of Victim link. Propagation model sub-sheet allows user to choose the suitable propagation model to be applied when calculating signal loss along the IT-VR path (when calculating unwanted signal - iRSS).

Propagation

Please see the separate information pages regarding the choice and settings of the propagation models.