| 7.1 | Use of these frequency bands shall require coordination with the neighbouring countries within the coordination zones of 50 kilometres 32 (specific to coordination between TETRA systems) from the neighbouring country. The coordination distance is continuously being reviewed and may be updated from time to time. |
| 7.1.1 | The following field strength thresholds have to be assured. Based on studies (ECC-Rep 97 32), a level of -114.7 dBm (=14.3 dBμV/m/25 kHz) is proposed as the threshold above which coordination between TETRA systems is required. The value is measured in a 25 kHz bandwidth and refers to a measuring height of 3 metres for duplex bands. |
| 7.1.2 | Operator-to-operator coordination may be necessary to avoid interference. |
| 7.2 | General indicative coordination thresholds for analogue or digital land mobile systems: |
| 7.2.1 | The aim of coordination thresholds is to avoid harmful interference between stations located in neighbouring countries. In order to achieve this, indicative coordination thresholds are established which should not be exceeded without coordination between neighbouring countries. |
| 7.2.2 | Indicative coordination threshold for land mobile systems (co-channel, 50% locations, 10% time 33, 10 m receiving antenna height, within a reference bandwidth of 25 kHz, at the borderline) is 18 dB (μV/m) for frequencies between 380 and 400 MHz; |
| 7.2.3 | For all other spectral power distributions, indicative coordination threshold levels should be applied within every 25 kHz bandwidth within the channel spacing. |
| 7.3 | For coordination thresholds for other systems and combinations of the systems, the following references may be considered: |
| 7.3.1 | ECC Report 97 provides coordination thresholds for several combinations of narrowband FM, TETRA, CDMA-PAMR, and Flash OFDM; |
| 7.3.2 | Annex 2 of ECC/DEC/ (08)/05 provides a list of related sharing and compatibility reports. |
| 7.3.3 | In case of coordination between LTE systems, Annex 5 of T/R 25-08 9 may be considered, unless newer LTE 380 studies become available. |
| 7.3.4 | As per ECC Report 276 34, “For historical reasons the Recommendation T/R 25-08 defines the trigger value at 10 m height. However, typically 3 m heights are considered for coordination of land mobile systems since the coverage is usually assumed for mobile user equipment. Furthermore, the definition of the trigger value at 3 m height is also easy applicable for drive tests (antenna at a vehicle’s roof). Recalculation of the derived thresholds from 3 m to 10 m height increases the coordination threshold by 15.6 dB”. |
| 7.3.4.1. | For systems using a channel spacing greater than 25 kHz, the following bandwidth conversion formula can be used provided that the spectral power distribution within this channel spacing is uniform within the channel. BC = 10 x log10 (channel spacing / 25 kHz), dB |
| 7.3.4.2. | The value (BC) resulting from the formula should be added to the indicative coordination threshold as listed above. |
To obtain the power level in wideband channel bandwidth, the BC resulting from the formula above should be added to the calculated threshold level (at 3 m or 10 m height) as calculated in 25 kHz bandwidth for the applicable preferential channel distance.
| 7.4 | In the event of any interference, the Authority will require affected parties to carry out coordination. In the event that the interference continues to be unresolved after 24 hours, the affected parties may refer the matter to the Authority for a resolution. The Authority will decide the necessary modifications and schedule of modifications to resolve the dispute. The Authority will be guided by the interference resolution process as shown in Appendix B. |
| 7.5 | Assignment holders shall take full advantage of interference mitigation techniques such as antenna discrimination, tilt, polarisation, frequency discrimination, shielding/blocking (introduce diffraction loss), site selection, and/or power control to facilitate the coordination of systems. |
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| 9 | ECC Recommendation T/R 25-08 Planning criteria and cross-border coordination of frequencies for land mobile systems in the range 29.7-470 MHz. Approved 15 January 1990. Amended 28 September 2018. Available online at https://docdb.cept.org/download/2544 |
| 32 | ECC Report 097 “Cross Border Interference for Land Mobile Technologies”, Bern, February 2007 https://docdb.cept.org/download/428 |
| 33 | In certain situations, the 1% time curves should be used for digital systems, e.g. to better protect analogue systems. |
| 34 | ECC Report 276 Thresholds for the coordination of CDMA and LTE broadband systems in the 400 MHz band, 27 April 2018. Available online at https://docdb.cept.org/download/1324 . |
