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Relative location of victim receiver and interfering transmitter

Calculation of the relative location of the Victim Receiver (VR) and the Interfering Transmitter (IT), which belong to two different link pairs (victim link WT-VR and interferer link IT-WR), depends on the choice of the correlation mode set for the VR-IT path in the scenario:

• None, i.e. non-correlated mode
• Uniform density mode
• Closest interferer mode
• Correlated distance, in which case the relative location is explicitely defined by the dX/dY values given in the scenario.

The two first modes (i.e. None and uniform density) use the notion of simulation radius of the interfering transmitter which defines the circular area where the ITs are spread.

Non-correlated mode

If the correlation mode for the IT-VR path is set to None, the relative location is calculated as follows:

• Trial of the path distance factor according to the scenario setting for the VR-IT path;
• Calculation of the absolute distance as a product of the user-defined simulation radius (constant value defined by the user in VR-IT path settings) and the above path distance factor;
• Trial of the path azimuth angle according to the relevant distribution set in the scenario for VR-IT path. Based on that relative angle-distance information, the absolute positions could be established with reference to one known position (usually VR in this case).

Note: If in the VR-IT path settings, the Number of active transmitters is set to more than one, this will result in spatially-independent generation of the specified number of ITs, whereas the resulting total iRSS strength will be obtained by simple power summation of the individual iRSS signal values.

Uniform density mode

If the correlation mode for the VR-IT path is set to Uniform density, the relative location is calculated as follows:

• Trial of the path distance factor according to an implicit uniform polar distance distribution between 0 and 1;
• Calculation of absolute distance as product of the simulation radius for the VR-IT path (calculated as described below) and the above path distance factor;
• Trial of the path azimuth angle of the IT-VR path according to relevant distribution assigned to this parameter in VR-IT path scenario settings.

In this case the IT-VR path simulation radius is calculated at the very beginning of EGE cycle and applied in all snapshots:

where:

• n^active - number of active transmitters set in the scenario for IT-VR path;
• dens_it^active - calculated product of active transmitters density:

• dens_it - density of transmitters, 1/km2, user-defined parameter in the table Interferers density of VR-IT path;
• P_it - probability of transmission, user-defined parameter;
• activity_it(time) - user-defined temporal activity function (a look-up table). The time value used for calculation is specified in parameter time.
• time - parameter defining which of the values in the above activity function should be used in calculations (e.g. if the activityit(time) function contains three pairs: (1;0.5), (2;0.7), (3; 0.9), and the time parameter is set to 2, then the activityit(time) function will be returning value 0.7).

Based on that relative angle-distance information, the absolute positions could be established with reference to one known position (usually VR in this case).

Note: If in the VR-IT path settings, the Number of active transmitters is set to more than one, this will result in spatially-independent generation of the specified number of ITs, whereas the resulting total iRSS strength will be obtained by simple power summation of the individual iRSS signal values.

Closest interferer

If the correlation mode for the VR-IT path is set to Closest interferer, the relative location is calculated as follows :

• Trial of the path azimuth angle of the IT-VR path according to relevant distribution assigned to this parameter in VR-IT path scenario settings;
• Repeat trial of the absolute distance (not the distance factor) between VR-IT according to an implicit Rayleigh distribution, until the result of this trial produces value smaller than the protection distance specified in the scenario.