4.8 Protection distance

If a minimum protection distance  between the victim link receiver and interefering link transmitter is introduced then the simulation radius may then be calculated by using the following formula:

                                                                                    (Eq. 30)

Note: The calculation of the iRSS at each trial will be performed only if the location of the ILT satisfies the following condition .

Figure 133 presents how to set-up SEAMCAT (See also A13.2 for further details).

Figure 133: Setting up the protection distance related to the simulation radius with 1 active interferer

The simulation radius (see Figure 135) may then be calculated by using the following formula:

Figure 134: Calculated simulated radius

Figure 135: Calculation of the simulation radius and the iRSS_unwanted using the protection distance (for 1 active interferer)

If the distance between the VLR and the ILT is equal to the protection distance (0.5 km), then:

                        iRSS_unwanted = 33 (dBm) + 11 + 9 - (32.5 + 10 log(0.5 x 0.5) + 20 log(1000)) = -33.5dBm       

If the distance between the VLR and the ILT is equal to the simulation radius (0.531 km), then:

                        iRSS_unwanted = 33 (dBm) + 11 + 9 - (32.5 + 10 log(0.531 x 0.531) + 20 log(1000)) = -34 dBm

These results are in line with those depicted on Figure 135. We can then increase the number of active transmitters to 10 as shown in Figure 136.

Figure 136: Setting up the protection distance related to the simulation radius with 10 active interferer

The simulation radius may then be calculated by using the following formula (see Figure 137 for the result):

 = 0.75 km             

Figure 137: Calculation of the R_simu and the iRSS_unwanted using the protection distance
(for 10 active interferer)

If the distance between the VLR and a single ILT is equal to the protection distance, then:

                        iRSS_unwanted = 33 (dBm) + 11 + 9 - (32.5 + 10 log(0.5 x 0.5) + 20 log(1000)) = -33.5 dBm

If the distance between the VLR and a single ILT is equal to the simulation radius, then:

iRSS_unwanted = 33 (dBm) + 11 + 9 - (32.5 + 10 log(0.75 x 0.75) + 20 log(1000)) = -37 dBm

If 10 transmitters are deployed around the VLR then:

iRSS_unwanted = -37 (dBm) + 10 log(10) = -27 dBm and iRSS_unwanted = -33.5 (dBm) + 10 log(10) = -23.5 dBm

                        -27 dBm < iRSS_unwanted < -23.5 dBm (see Figure 137)