8 Radiated spurious emissions

3GPP51.021Base Station System (BSS) equipment specificationRadio aspectsRelease 17TS

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

8.1 Test Purpose

This test measures radiated spurious emissions from the BSS cabinet, including emissions due to the transmitters. For a BTS with multiple enclosures according to clause 8.2 the BTS part with Radio digital unit and the Radio unit may be tested separately in alignment with requirements specified for such equipment operating UTRA [32] or E-UTRA [33], respectively.

8.2 Test Case

a) A test site fulfilling the requirements of ITU-R SM.329-10 shall be used. The BTS shall be placed on a non‑conducting support and shall be operated from a power source via an RF filter to avoid radiation from the power leads. The method of ITU-R SM.329-10 shall be used, except in any case where it conflicts with the present document.

Radiation of any spurious components shall be detected by the test antenna and measuring receiver (e.g. a spectrum analyser). At each frequency at which a component is detected, the BSS shall be rotated and the height of the test antenna adjusted to obtain maximum response, and the effective radiated power of that component determined by a substitution measurement. The measurement shall be repeated with the test antenna in the orthogonal polarization plane.

For BTS with single enclosure solution according to Fig. 8.2-1 and Fig. 8.2-2, radiated spurious emissions are measured from the BSS cabinet including emissions due to the transmitters from the radio equipment.

For BTS with multiple enclosure solution according to Fig. 8.2-1 and Fig. 8.2-3, radiated spurious emissions from the BTS part with radio digital unit and the radio unit may be tested separately.

The definition of enclosure port is aligned to [32] and [33] and is depicted below in Fig. 8.2-1. Further definitions are included in clause 3.1.

NOTE: For example, any connection point on an equipment intended for connection of cables to or from that equipment is considered as a port (see Fig. 8.2-1).

Figure 8.2-1: Examples of ports

Figure 8.2-2: BTS with single enclosure solution

Figure 8.2-3: BTS with multiple enclosure solution

b) The BTS shall be configured with one transmitter active, at its maximum output power on all time slots, on the specified ARFCNs. Slow frequency hopping shall be disabled.

NOTE: It may be necessary to take steps to ensure that emissions from other transmitters which are not active do not influence the results. This may be achieved by, for example, equipping the BTS with only one TRX or by muting the outputs of the transmitters to a greater degree than otherwise required in 3GPP TS 05.05 or 3GPP TS 45.005.

c) The measuring receiver shall be configured with a resolution bandwidth of 30 kHz and a video bandwidth of approximately three times this value. Peak hold shall be enabled, except in case of multicarrier BTS where RMS detector mode applies. The received power shall be measured for frequencies with an offset of 1.8 MHz  f < 6 MHz from the carrier frequency, and which fall within the BTS relevant transmitter band.

At each frequency at which a component is detected, the maximum effective radiated power of that component shall be determined, as described in step a).

d) The measuring receiver shall be configured with a resolution bandwidth of 100 kHz and a video bandwidth of approximately three times this value. Peak hold shall be enabled, except in case of multicarrier BTS where RMS detector mode applies. The received power shall be measured for frequencies with an offset of 6 MHz from the carrier frequency, and which fall within the BTS relevant transmitter band.

At each frequency at which a component is detected, the maximum effective radiated power of that component shall be determined, as described in step a).

e) The BSS shall be configured with all transmitters active at their maximum output power on all time slots. If a TRX is designated as being a dedicated BCCH, it shall be allocated to RF channel M. All remaining TRXs shall be allocated in the following order; first to RF channel B, then to T, then distributed as evenly as possible throughout the BSS operating transmit band. Slow frequency hopping shall be disabled.
In case of multicarrier BTS the maximum number of supported carriers are active and operating at maximum declared power. The carriers are distributed over the maximum supported RF BW as defined in subclause 6.12.

The measuring receiver shall be configured as defined in table 8-1. Peak hold shall be enabled, and the video bandwidth shall be approximately three times the resolution bandwidth. If this video bandwidth is not available on the measuring receiver, it shall be the maximum available, and at least 1 MHz. In case of multicarrier BTS the RMS detector mode applies instead. The received power shall be measured over the frequency range 30 MHz to 12,75 GHz, excluding the BTS relevant transmitter band.

Table 8-1: Radiated spurious Emissions Measurements outside the transmit band

Frequency Band	Frequency offset	Resolution Bandwidth
30 MHz ‑ 50 MHz		10 kHz
50 MHz ‑ 500 MHz and outside the relevant transmit band	(offset from the edge of the relevant transmit band)
	 2 MHz	30 kHz
	 5 MHz	100 kHz
500 MHz ‑ 1 GHz and outside the relevant transmit band	(offset from the edge of the relevant transmit band)
	2 MHz	30 kHz
	5 MHz	100 kHz
	10 MHz	300 kHz
	20 MHz	1 MHz
	30 MHz	3 MHz
1 GHz ‑ 12,75 GHz and outside the relevant transmit band	(offset from the edge of the relevant transmit band)
	2 MHz	30 kHz
	5 MHz	100 kHz
	10 MHz	300 kHz/ 1 MHz^(NOTE)
	20 MHz	1 MHz
	30 MHz	3 MHz
NOTE: 1 MHz measurement bandwidth applies only to BTS belonging to a multicarrier BTS class

At each frequency at which a component is detected, the maximum effective radiated power of that component shall be determined, as described in step a).

8.3 Void

8.4 Conformance requirement

Test Environment:

Normal: Inside the relevant TX band: The test shall be performed three times with the TRX on one of the RF channels B, M, and T.

Outside the relevant TX band: The test shall be repeated until a measurement has been made with a TRX active on B, M and T.

NOTE: For a BSS with 3 or more TRX, this requires only one measurement.

Minimum Requirement

a) The power measured at steps c) and d) shall not exceed ‑36 dBm.

b) The power measured at step e) shall not exceed:

‑36 dBm for frequencies up to 1 GHz.

‑30 dBm for frequencies above 1 GHz.

8.5 Requirement reference

3GPP TS 45.005, subclause 4.3.