# 6.3 Input system parameters

For the sensing feature to be activated, both the victim and interferer transmitters have to have the “interferer is <span data-highlighted="true" data-vc="highlighted-text"><span class="_kqswh2mm"><span class="_5pioz8co _189e1dm9 _1il9buyh _19lc184f _d0altlke" data-testid="definition-highlighter">CR</span></span></span>” selected (Figure 158). This will activate the spectrum sensing algorithm (see ANNEX 16:) and will allow you to set the transmitting characteristic of the victim link transmitter, i.e. the energy that the cognitive radio spectrum sensing device is to sense. You will be able to set the emission mask and the emission floor.

[![image.png](https://wiki.cept.org/uploads/images/gallery/2026-04/scaled-1680-/yM8eC2RmrzzMb1rS-image.png)](https://wiki.cept.org/uploads/images/gallery/2026-04/yM8eC2RmrzzMb1rS-image.png)

<div class="rich-media-item mediaSingleView-content-wrap image-align-start css-jammtw" data-layout="align-start" data-media-vc-wrapper="true" data-node-type="mediaSingle" data-renderer-start-pos="448" data-vc="media-single" data-width="901" data-width-type="pixel" id="bkmrk-figure-158%3A-selectio"><div class="css-ca0th7"><div data-alt="" data-collection="contentId-494331" data-context-id="494331" data-file-mime-type="" data-file-name="file" data-file-size="1" data-height="316" data-id="ae604724-079c-425f-a2ff-842805d2dbff" data-node-type="media" data-renderer-start-pos="449" data-type="file" data-width="1140"><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-158%3A-selectio-1"><div class="_1reo15vq _18m915vq _2rko18qm _1e0c1txw _kqswh2mm _p12f1osq _1bsb1osq _4t3i1osq _c71l1osq media-file-card-view" data-cursor="pointer" data-test-media-name="58.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/6a16ee6f-ab40-4bca-9322-9c0f1365cf0d#media-blob-url=true&id=ae604724-079c-425f-a2ff-842805d2dbff&collection=contentId-494331&contextId=494331&width=1140&height=316&alt=&clientId=113268fe-fe5b-4bc3-8ff3-07965dbf1d18)**Figure 158: Selection of the <span data-highlighted="true" data-vc="highlighted-text">CR</span> algorithm**</div></div></div></div></div></div>**Table 20: Victim Link transmitter**

<div class="pm-table-container with-shadow-observer" data-layout="align-start" data-testid="table-container" id="bkmrk-description-symbol-t"><div class="pm-table-wrapper" data-autosize="false" data-layout="align-start" data-number-column="false" data-table-local-id="" data-vc="table-node-wrapper"><table data-layout="align-start" data-number-column="false" data-table-width="760" data-testid="renderer-table" style="width: 100%;"><colgroup></colgroup><tbody><tr><td colspan="1" rowspan="1" style="width: 16.2059%;">**Description**

</td><td colspan="1" rowspan="1" style="width: 8.57869%;">**Symbol**

</td><td colspan="1" rowspan="1" style="width: 9.65296%;">**Type**

</td><td colspan="1" rowspan="1" style="width: 11.3203%;">**Unit**

</td><td colspan="1" rowspan="1" style="width: 54.2183%;">**Comments**

</td></tr><tr><td colspan="1" rowspan="1" style="width: 16.2059%;">Interferer is <span data-highlighted="true" data-vc="highlighted-text">CR</span>

</td><td colspan="1" rowspan="1" style="width: 8.57869%;"></td><td colspan="1" rowspan="1" style="width: 9.65296%;">switch

</td><td colspan="1" rowspan="1" style="width: 11.3203%;"></td><td colspan="1" rowspan="1" style="width: 54.2183%;">When the <span data-highlighted="true" data-vc="highlighted-text">CR</span> button is checked then it allows to set the emission characteristics of the VLT (used for the sRSS calculation only)

</td></tr><tr><td colspan="1" rowspan="1" style="width: 16.2059%;">Emission mask:

Unwanted signal level (VLT)

</td><td colspan="1" rowspan="1" style="width: 8.57869%;"></td><td colspan="1" rowspan="1" style="width: 9.65296%;">Function (X,Y) (MHz)

</td><td colspan="1" rowspan="1" style="width: 11.3203%;">dBm/reference bandw. (MHz)

</td><td colspan="1" rowspan="1" style="width: 54.2183%;">Define the mask of the transmitter, in the emission bandwidth and out of the emission bandwidth.

Negative values in the relative mask should be chosen in a way that the integration over the emission bandwidth results in the total emitted power. If constant mask, there is no emission outside of the bandwidth.

</td></tr><tr><td colspan="1" rowspan="1" style="width: 16.2059%;">Unwanted emissions floor: Noise floor signal level

</td><td colspan="1" rowspan="1" style="width: 8.57869%;"></td><td colspan="1" rowspan="1" style="width: 9.65296%;">Function (X,Y) (MHz)

</td><td colspan="1" rowspan="1" style="width: 11.3203%;">dBm/

reference bandw. (MHz)

</td><td colspan="1" rowspan="1" style="width: 54.2183%;">Define the minimum strength of the unwanted emissions.

So the unwanted emissions equal to Max(Pwt + Unwanted emission, Unwanted emissions floor)

</td></tr></tbody></table>

<div class="sentinel-right">  
</div></div><div class="pm-table-sticky-scrollbar-container-view-page" data-vc="table-sticky-scrollbar-container"></div></div> Note that the settings of the emissions mask and the emission floor is the same as for the interfering link (i.e. same units).

![image.png](https://wiki.cept.org/uploads/images/gallery/2026-04/scaled-1680-/fL2ExCGwmnBJTKYF-image.png)

![image.png](https://wiki.cept.org/uploads/images/gallery/2026-04/scaled-1680-/CuTNyN0AvUdcsNO0-image.png)

**Figure 159: Activate the <span data-highlighted="true" data-vc="highlighted-text">CR</span> in the VLT (Victim Link) to consider its emission characteristics**   
 **(i.e. used in the sRSS calculation)**