6.7 Transmitter intermodulation

37.1043GPPMulti-Standard Radio (MSR) Base Station (BS) radio transmission and receptionNR, E-UTRA, UTRA and GSM/EDGERelease 17TS

Tools: ARFCN - Frequency Conversion for 5G NR/LTE/UMTS/GSM

The transmitter intermodulation requirement is a measure of the capability of the transmitter to inhibit the generation of signals in its non-linear elements caused by presence of the wanted signal and an interfering signal reaching the transmitter via the antenna. The requirement applies during the transmitter ON period and the transmitter transient period.

For BS capable of multi-band operation where multiple bands are mapped on separate antenna connectors, the single-band requirements apply regardless of the interfering signals position relative to the Inter-RF Bandwidth gap.

6.7.1 General minimum requirement

The transmitter intermodulation level is the power of the intermodulation products when an interfering signal is injected into the antenna connector.

The transmitter intermodulation level shall not exceed the unwanted emission limits in subclause 6.6.1, 6.6.2, 6.6.4 in the presence of a wanted signal and an interfering signal according to Table 6.7.1‑1 for BS operation in BC1, BC2 and BC3.

The requirement is applicable outside the Base Station RF Bandwidth or Radio Bandwidth. The interfering signal offset is defined relative to the Base Station RF Bandwidth edges or Radio Bandwidth edges.

For BS operating in non-contiguous spectrum, the requirement is also applicable inside a sub-block gap for interfering signal offsets where the interfering signal falls completely within the sub-block gap. The interfering signal offset is defined relative to the sub-block edges.

For BS capable of multi-band operation, the requirement applies relative to the Base Station RF Bandwidth edges of each operating band. In case the Inter RF Bandwidth gap is less than 15 MHz, the requirement in the gap applies only for interfering signal offsets where the interfering signal falls completely within the Inter RF Bandwidth gap.

Table 6.7.1-1: Interfering signals for the Transmitter intermodulation requirement

Parameter	Value
Interfering signal type	E-UTRA signal of channel bandwidth 5 MHz
Interfering signal level	Rated total output power in the operating band – 30dB
Interfering signal centre frequency offset from the Base Station RF Bandwidth edge or sub-block edge inside a gap	±2.5 MHz ±7.5 MHz ±12.5 MHz
NOTE 1: Interfering signal positions that are partially or completely outside of any downlink operating band of the base station are excluded from the requirement, unless the interfering signal positions fall within the frequency range of adjacent downlink operating bands in the same geographical area. In case that none of the interfering signal positions fall completely within the frequency range of the downlink operating band, TS 37.141 [10] provides further guidance regarding appropriate test requirements. NOTE 2: In certain regions, NOTE 1 is not applied in Band 1, 3, 8, 9, 11, 18, 19, 21, 28, 32 operating within 1475.9-1495.9MHz, 34.

6.7.2 Additional minimum requirement (BC1 and BC2)

The requirement is applicable outside the Base Station RF Bandwidth and Radio Bandwidth for BC2. The interfering signal offset is defined relative to the Base Station RF Bandwidth edges or Radio Bandwidth edges.

For BS operating in non-contiguous spectrum in BC1 or BC2, the requirement is also applicable inside a sub-block gap with a gap size larger than or equal to two times the interfering signal centre frequency offset. For BS operating in non-contiguous spectrum in BC1, the requirement is not applicable inside a sub-block gap with a gap size equal to or larger than 5 MHz. The interfering signal offset is defined relative to the sub-block edges.

For BS capable of multi-band operation, the requirement applies relative to the Base Station RF Bandwidth edges of a BC2 operating band. The requirement is also applicable for BC1 and BC2 inside an Inter RF Bandwidth gap equal to or larger than two times the interfering signal centre frequency offset. For BS capable of multi-band operation, the requirement is not applicable for BC1 band inside an Inter RF Bandwidth gap with a gap size equal to or larger than 5 MHz.

Table 6.7.2-1: Interfering signal for the transmitter intermodulation requirement

Parameter	Value
Interfering signal type	CW
Interfering signal level	Rated total output power in the operating band – 30dB
Interfering signal centre frequency offset from the Base Station RF Bandwidth edge or sub-block edge inside a gap	> abs(800) kHz for CW interferer
NOTE: Interfering signal positions that are partially or completely outside of any downlink operating band of the base station are excluded from the requirement.

6.7.3 Additional minimum requirement (BC3)

For BS capable of multi-band operation, the requirement applies relative to the Base Station RF Bandwidth edges of each operating band. In case the Inter RF Bandwidth gap is less than 3.2 MHz, the requirement in the gap applies only for interfering signal offsets where the interfering signal falls completely within the Inter RF Bandwidth gap.

Table 6.7.3-1: Interfering signals for the Transmitter intermodulation requirement (BC3)

Parameter	Value
Interfering signal type	1.28Mcps UTRA TDD signal of channel bandwidth 1.6MHz
Interfering signal level	Rated total output power in the operating band – 30dB
Interfering signal centre frequency offset from Base Station RF Bandwidth edge or sub-block edge inside a gap	±0.8 MHz ±1.6 MHz ±2.4 MHz
NOTE: Interfering signal positions that are partially or completely outside of any downlink operating band of the base station are excluded from the requirement.

6.7.4 Additional requirements

In certain regions the following requirement may apply. For BS E-UTR single-RAT operating in Band 41, the transmitter intermodulation level shall not exceed the maximum levels specified in Table 6.6.1.3.1-3 and Table 6.6.4.1-2 with a square filter in the first adjacent channel, in the presence of an interfering signal according to Table 6.7.4‑1.

Table 6.7.4-1 Interfering and wanted signals for the additional transmitter intermodulation requirement for Band 41

Parameter	Value
Wanted signal	E-UTRA single carrier (NOTE)
Interfering signal type	E-UTRA signal of the same channel bandwidth as the wanted signal
Interfering signal level	Rated total output power in the operating band – 30dB
Interfering signal centre frequency offset from the lower/upper centre frequency of the wanted signal	± BW_Channel ± 2 x BW_Channel
NOTE: This requirement applies for 10 or 20 MHz E-UTRA carriers allocated within 2545-2645 MHz.