4 Parameters used to determine IMT base-station relative antenna gain due to antenna downtilt Parameter Azimuth angle 0 degrees Elevation angle 0 degrees Horizontal 3 dB 65 degrees beamwidth Vertical 3 dB 9.1 degrees beamwidth 0.3 k Downtilt 3 degrees Average relative dB –1.9 gain Peak relative dB –1.22 gain 3.2.3 Additional parameters The following additional parameters are used to determine separation distances: Broadcasting protection criteria, = dB. I/N – –10 For specific application scenarios, directivity discrimination may be considered. Report ITUR BT.2265 provides methodologies for discrimination as well as multiple interferers. It should be noted that multiple interferers on various DTTB frequencies may be significant. It has been reported, that combinations of undesired signals can cause interference on a desired DTTB channel. For example, as reported, if the desired DTTB channel is signals on channels + and N, N K + 2K, where is an integer between 1 and 10, will combine to cause interference into the desired N K channel These results have confirmed with the observation of single and double interferers on N. frequencies near the DTTB channel. 4 Analysis 4.1 Assumptions A single interferer is assumed. – Peak interference power is used since the minimum noise burst duration performance for – the DTTB System A is 165 microseconds (per Recommendation ITU-R BT.2036). Propagation curves for one percent time variability are used for interference thresholds. – Propagation over land is assumed; sea paths are not considered. – No specific terrain information is implied so a representative clutter height of 10 m is used. – Polarisation discrimination is not considered. – DTTB System A channel frequency for this study is 692 to 698 MHz. – DTTB elevation pattern per Recommendation ITU-R BT.419 does not impact the required – separation distances between the IMT UE and a fixed DTTB receiving system for horizontal separations greater than 24 m.
4 Parameters used to determine IMT base-station relative antenna gain due to antenna downtilt Parameter Azimuth angle 0 degrees Elevation angle 0 degrees Horizontal 3 dB beamwidth 65 degrees Vertical 3 dB beamwidth 9.1 degrees k 0.3 Downtilt 3 degrees Average relative gain –1.9 dB Peak relative gain –1.22 dB 3.2.3 Additional parameters The following additional parameters are used to determine separation distances: – Broadcasting protection criteria, I/N = –10 dB. For specific application scenarios, directivity discrimination may be considered. Report ITUR BT.2265 provides methodologies for discrimination as well as multiple interferers. It should be noted that multiple interferers on various DTTB frequencies may be significant. It has been reported, that combinations of undesired signals can cause interference on a desired DTTB channel. For example, as reported, if the desired DTTB channel is N, signals on channels N + K and N + 2K, where K is an integer between 1 and 10, will combine to cause interference into the desired channel N. These results have confirmed with the observation of single and double interferers on frequencies near the DTTB channel. 4 Analysis 4.1 Assumptions – A single interferer is assumed. – Peak interference power is used since the minimum noise burst duration performance for the DTTB System A is 165 microseconds (per Recommendation ITU-R BT.2036). – Propagation curves for one percent time variability are used for interference thresholds. – Propagation over land is assumed; sea paths are not considered. – No specific terrain information is implied so a representative clutter height of 10 m is used. – Polarisation discrimination is not considered. – DTTB System A channel frequency for this study is 692 to 698 MHz. – DTTB elevation pattern per Recommendation ITU-R BT.419 does not impact the required separation distances between the IMT UE and a fixed DTTB receiving system for horizontal separations greater than 24 m.
R-REP-BT.2337-2014-MSW-E.docx