# 4.8 Protection distance

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

[![image.png](https://wiki.cept.org/uploads/images/gallery/2026-04/scaled-1680-/pwgpa7jGvwzhp4Id-image.png)](https://wiki.cept.org/uploads/images/gallery/2026-04/pwgpa7jGvwzhp4Id-image.png) *(Eq. 30)*

Note: The calculation of the iRSS at each trial will be performed only if the location of the <span data-highlighted="true" data-vc="highlighted-text"><span class="_kqswh2mm"><span class="_5pioz8co _189e1dm9 _1il9buyh _19lc184f _d0altlke" data-testid="definition-highlighter">ILT</span></span></span> satisfies the following condition[![image.png](https://wiki.cept.org/uploads/images/gallery/2026-04/scaled-1680-/TjRdjTaR2Noryw4a-image.png)](https://wiki.cept.org/uploads/images/gallery/2026-04/TjRdjTaR2Noryw4a-image.png).

Figure 129 presents how to set-up SEAMCAT (See also A13.2 for further details).

[![image.png](https://wiki.cept.org/uploads/images/gallery/2026-04/scaled-1680-/I56kzfMBz4PrxcYi-image.png)](https://wiki.cept.org/uploads/images/gallery/2026-04/I56kzfMBz4PrxcYi-image.png)

<div class="rich-media-item mediaSingleView-content-wrap image-align-start css-1dsd1wq" data-layout="align-start" data-media-vc-wrapper="true" data-node-type="mediaSingle" data-renderer-start-pos="511" data-vc="media-single" data-width="214" data-width-type="pixel" id="bkmrk-figure-129%3A-setting-"><div class="css-4bpi6l"><div data-alt="" data-collection="contentId-494292" data-context-id="494292" data-file-mime-type="image/png" data-file-name="129.png" data-file-size="29645" data-height="524" data-id="d5b5b928-8d83-4edd-bc88-d045390f41ac" data-node-type="media" data-renderer-start-pos="512" data-type="file" data-width="450"><div class="_2rko18qm _vchhusvi _kqswh2mm _ect4ttxp _p12f1osq _c71l1osq _1bsb1qmm _4t3ine4n _1hlmd0i9 _1rquusvi _eg541i5c _mts3kb7n _1ntskb7n _yfmhtlke _5sb1v00u new-file-experience-wrapper" data-media-vc-wrapper="true" data-testid="media-card-view" id="bkmrk-figure-129%3A-setting--1"><div class="_1reo15vq _18m915vq _2rko18qm _1e0c1txw _kqswh2mm _p12f1osq _1bsb1osq _4t3i1osq _c71l1osq media-file-card-view" data-cursor="pointer" data-test-media-name="129.png" data-test-progress="1" data-test-source="remote" data-test-status="complete" data-testid="media-file-card-view"><div class="_kqswstnw _1bsb1osq _4t3i1osq _1e0c1txw _2lx21bp4 _1bah1h6o _4cvr1h6o align-center" data-testid="ImageRendererWrapper">![](blob:https://ecowiki.atlassian.net/4500dd30-f20e-42bd-9d25-ce6681ab2dde#media-blob-url=true&id=d5b5b928-8d83-4edd-bc88-d045390f41ac&collection=contentId-494292&contextId=494292&width=450&height=524&alt=&clientId=113268fe-fe5b-4bc3-8ff3-07965dbf1d18)**Figure 129: Setting up the protection distance related to the simulation radius with 1 active interferer**</div></div></div></div></div></div>The simulation radius (see Figure 131) may then be calculated by using the following formula:

[![image.png](https://wiki.cept.org/uploads/images/gallery/2026-04/scaled-1680-/TB0VHNJzFkdblD1q-image.png)](https://wiki.cept.org/uploads/images/gallery/2026-04/TB0VHNJzFkdblD1q-image.png)

<div class="rich-media-item mediaSingleView-content-wrap image-align-start css-19refa8" data-layout="align-start" data-media-vc-wrapper="true" data-node-type="mediaSingle" data-renderer-start-pos="721" data-vc="media-single" data-width="503" data-width-type="pixel" id="bkmrk--3"><div class="css-16yc0sg"><div data-alt="" data-collection="contentId-494292" data-context-id="494292" data-file-mime-type="image/png" data-file-name="130.png" data-file-size="5538" data-height="94" data-id="fb122361-adac-4c2a-9669-8fda71f07093" data-node-type="media" data-renderer-start-pos="722" data-type="file" data-width="503"><div class="_2rko18qm _vchhusvi _kqswh2mm _ect4ttxp _p12f1osq _c71l1osq _1bsb1qmm _4t3ine4n _1hlmd0i9 _1rquusvi _eg541i5c _mts3kb7n _1ntskb7n _yfmhtlke _5sb1v00u new-file-experience-wrapper" data-media-vc-wrapper="true" data-testid="media-card-view" id="bkmrk--4"><div class="_1reo15vq _18m915vq _2rko18qm _1e0c1txw _kqswh2mm _p12f1osq _1bsb1osq _4t3i1osq _c71l1osq media-file-card-view" data-cursor="pointer" data-test-media-name="130.png" data-test-progress="1" data-test-source="remote" data-test-status="complete" data-testid="media-file-card-view">  
</div></div></div></div></div><div class="fabric-editor-block-mark fabric-editor-alignment" data-align="center" id="bkmrk--5"></div><div class="fabric-editor-block-mark fabric-editor-alignment" data-align="center" id="bkmrk--6"></div>[![image.png](https://wiki.cept.org/uploads/images/gallery/2026-04/scaled-1680-/wejZFOOKud5ggpOl-image.png)](https://wiki.cept.org/uploads/images/gallery/2026-04/wejZFOOKud5ggpOl-image.png)

<div class="fabric-editor-block-mark fabric-editor-alignment align-center" data-align="center" id="bkmrk-figure-130%3A-calculat">**Figure 130: Calculated simulated radius**</div>![image.png](https://wiki.cept.org/uploads/images/gallery/2026-04/scaled-1680-/olTR3bzsJKWjBPb7-image.png)

<div class="rich-media-item mediaSingleView-content-wrap image-align-start css-1fcvn4m" data-layout="align-start" data-media-vc-wrapper="true" data-node-type="mediaSingle" data-renderer-start-pos="768" data-vc="media-single" data-width="463" data-width-type="pixel" id="bkmrk-figure-131%3A-calculat"><div class="css-lxubws"><div data-alt="" data-collection="contentId-494292" data-context-id="494292" data-file-mime-type="image/png" data-file-name="131.png" data-file-size="79449" data-height="475" data-id="f4ae506d-be45-41fd-a22b-71a61588bcab" data-node-type="media" data-renderer-start-pos="769" data-type="file" data-width="880"><div class="_2rko18qm _vchhusvi _kqswh2mm _ect4ttxp _p12f1osq _c71l1osq _1bsb1qmm _4t3ine4n _1hlmd0i9 _1rquusvi _eg541i5c _mts3kb7n _1ntskb7n _yfmhtlke _5sb1v00u new-file-experience-wrapper" data-media-vc-wrapper="true" data-testid="media-card-view" id="bkmrk-figure-131%3A-calculat-1"><div class="_1reo15vq _18m915vq _2rko18qm _1e0c1txw _kqswh2mm _p12f1osq _1bsb1osq _4t3i1osq _c71l1osq media-file-card-view" data-cursor="pointer" data-test-media-name="131.png" data-test-progress="1" data-test-source="remote" data-test-status="complete" data-testid="media-file-card-view"><div class="_kqswstnw _1bsb1osq _4t3i1osq _1e0c1txw _2lx21bp4 _1bah1h6o _4cvr1h6o align-center" data-testid="ImageRendererWrapper">![](blob:https://ecowiki.atlassian.net/692d1389-878c-45a2-8e75-fd852a889c94#media-blob-url=true&id=f4ae506d-be45-41fd-a22b-71a61588bcab&collection=contentId-494292&contextId=494292&mimeType=image%2Fpng&name=131.png&size=79449&width=880&height=475&alt=&clientId=113268fe-fe5b-4bc3-8ff3-07965dbf1d18)**Figure 131: Calculation of the simulation radius and the iRSS<sub data-renderer-mark="true">unwanted</sub> using the protection distance (*****for 1 active interferer*****)**</div></div></div></div></div></div>If the distance between the <span data-highlighted="true" data-vc="highlighted-text"><span class="_kqswh2mm"><span class="_5pioz8co _189e1dm9 _1il9buyh _19lc184f _d0altlke" data-testid="definition-highlighter">VLR</span></span></span> and the <span data-highlighted="true" data-vc="highlighted-text">ILT</span> is equal to the protection distance (0.5 km), then:

 [![image.png](https://wiki.cept.org/uploads/images/gallery/2026-04/scaled-1680-/7kNdDJc7jZjPjPsF-image.png)](https://wiki.cept.org/uploads/images/gallery/2026-04/7kNdDJc7jZjPjPsF-image.png)

If the distance between the <span data-highlighted="true" data-vc="highlighted-text">VLR</span> and the <span data-highlighted="true" data-vc="highlighted-text">ILT</span> is equal to the simulation radius (0.531 km), then:

 [![image.png](https://wiki.cept.org/uploads/images/gallery/2026-04/scaled-1680-/bKY9chLl8plNC8bT-image.png)](https://wiki.cept.org/uploads/images/gallery/2026-04/bKY9chLl8plNC8bT-image.png)

These results are in line with those depicted on Figure 131. We can then increase the number of active transmitters to 10 as shown in Figure 132.

[![image.png](https://wiki.cept.org/uploads/images/gallery/2026-04/scaled-1680-/Q5mewLud0E5vG5Hv-image.png)](https://wiki.cept.org/uploads/images/gallery/2026-04/Q5mewLud0E5vG5Hv-image.png)

<div class="rich-media-item mediaSingleView-content-wrap image-align-start css-1dsd1wq" data-layout="align-start" data-media-vc-wrapper="true" data-node-type="mediaSingle" data-renderer-start-pos="1307" data-vc="media-single" data-width="214" data-width-type="pixel" id="bkmrk-figure-132%3A-setting-"><div class="css-igtd6u"><div data-alt="" data-collection="contentId-494292" data-context-id="494292" data-file-mime-type="image/png" data-file-name="132.png" data-file-size="29849" data-height="527" data-id="767fa5cd-0bac-4fe6-9948-40753a329aaf" data-node-type="media" data-renderer-start-pos="1308" data-type="file" data-width="452"><div class="_2rko18qm _vchhusvi _kqswh2mm _ect4ttxp _p12f1osq _c71l1osq _1bsb1qmm _4t3ine4n _1hlmd0i9 _1rquusvi _eg541i5c _mts3kb7n _1ntskb7n _yfmhtlke _5sb1v00u new-file-experience-wrapper" data-media-vc-wrapper="true" data-testid="media-card-view" id="bkmrk-figure-132%3A-setting--1"><div class="_1reo15vq _18m915vq _2rko18qm _1e0c1txw _kqswh2mm _p12f1osq _1bsb1osq _4t3i1osq _c71l1osq media-file-card-view" data-cursor="pointer" data-test-media-name="132.png" data-test-progress="1" data-test-source="remote" data-test-status="complete" data-testid="media-file-card-view"><div class="_kqswstnw _1bsb1osq _4t3i1osq _1e0c1txw _2lx21bp4 _1bah1h6o _4cvr1h6o align-center" data-testid="ImageRendererWrapper">![](blob:https://ecowiki.atlassian.net/084a8796-2c4d-4531-8dc3-9c5a2e90806e#media-blob-url=true&id=767fa5cd-0bac-4fe6-9948-40753a329aaf&collection=contentId-494292&contextId=494292&mimeType=image%2Fpng&name=132.png&size=29849&width=452&height=527&alt=&clientId=113268fe-fe5b-4bc3-8ff3-07965dbf1d18)**Figure 132: Setting up the protection distance related to the simulation radius with 10 active interferer**</div></div></div></div></div></div>The simulation radius may then be calculated by using the following formula (see Figure 133 for the result):

 [![image.png](https://wiki.cept.org/uploads/images/gallery/2026-04/scaled-1680-/pv3sdy5GazLQO9wg-image.png)](https://wiki.cept.org/uploads/images/gallery/2026-04/pv3sdy5GazLQO9wg-image.png)

![image.png](https://wiki.cept.org/uploads/images/gallery/2026-04/scaled-1680-/IUipPHwEIawrS2vE-image.png)**Figure 133: Calculation of the R<sub data-renderer-mark="true">simu</sub> and the iRSS<sub data-renderer-mark="true">unwanted</sub> using the protection distance**   
 **(*****for 10 active interferer*****)**

If the distance between the <span data-highlighted="true" data-vc="highlighted-text">VLR</span> and a single <span data-highlighted="true" data-vc="highlighted-text">ILT</span> is equal to the protection distance, then:

 [![image.png](https://wiki.cept.org/uploads/images/gallery/2026-04/scaled-1680-/pOpLzDjuY2wdeRRo-image.png)](https://wiki.cept.org/uploads/images/gallery/2026-04/pOpLzDjuY2wdeRRo-image.png)

If the distance between the <span data-highlighted="true" data-vc="highlighted-text">VLR</span> and a single <span data-highlighted="true" data-vc="highlighted-text">ILT</span> is equal to the simulation radius, then:

[![image.png](https://wiki.cept.org/uploads/images/gallery/2026-04/scaled-1680-/mQKnfQhcrwMrs2QP-image.png)](https://wiki.cept.org/uploads/images/gallery/2026-04/mQKnfQhcrwMrs2QP-image.png)

If 10 transmitters are deployed around the <span data-highlighted="true" data-vc="highlighted-text">VLR</span> then:

[![image.png](https://wiki.cept.org/uploads/images/gallery/2026-04/scaled-1680-/GBABDSpjusnHin5B-image.png)](https://wiki.cept.org/uploads/images/gallery/2026-04/GBABDSpjusnHin5B-image.png) and

[![image.png](https://wiki.cept.org/uploads/images/gallery/2026-04/scaled-1680-/a0upNbBP9IkyLQ7z-image.png)](https://wiki.cept.org/uploads/images/gallery/2026-04/a0upNbBP9IkyLQ7z-image.png)

[![image.png](https://wiki.cept.org/uploads/images/gallery/2026-04/scaled-1680-/ACjfhTVThiN8Oyqu-image.png)](https://wiki.cept.org/uploads/images/gallery/2026-04/ACjfhTVThiN8Oyqu-image.png)  *(see Figure 133)*