8 Out of band gain

25.1533GPPRelease 17TSUTRA repeater conformance testing (LCR TDD)

8.1 Definitions and applicability

Out of band gain refers to the gain of the Repeater immediately outside the pass band. The measurements shall apply to both paths uplink and downlink of the Repeater.

8.2 Minimum requirement

The intended use of a repeater in a system is to amplify the in band signals and not to amplify the out of band emission of the donor base station.

In the intended application of the repeater, the out of band gain is less than the donor coupling loss.

The repeater minimum donor coupling loss shall be declared by the manufacturer. This is this the minimum required attenuation between the donor BS and the repeater for proper repeater operation.

The gain outside the pass band shall not exceed the maximum level specified in table 8.1, where:

– f_offset is the distance from the centre frequency of the first or last channel within the pass band.

Table 8.1: Out of band gain limits 1

Frequency offset from the carrier frequency, f_offset	Maximum gain
1,0  f_offset < 1,8 MHz	60 dB
1,8  f_offset < 5,8 MHz	45 dB
5,8  f_offset < 10,8 MHz	45 dB
10,8 MHz  f_offset	35 dB

For 10,8 MHz  f_offset the out of band gain shall not exceed the maximum gain of table 8.2 or the maximum gain stated in table 8.1 whichever is lower.

Table 8.2: Out of band gain limits 2

Repeater maximum output power as in 9.1.1.1	Maximum gain
P < 31 dBm	Out of band gain  minimum donor coupling loss
31 dBm  P < 43 dBm	Out of band gain  minimum donor coupling loss
P  43 dBm	Out of band gain  minimum donor coupling loss – (P-43dBm)
NOTE 1: The out of band gain is considered with 10,8 MHz  f_offset

8.3 Test purpose

The purpose of this test is to verify that the Repeater meets the out of band gain requirements as specified by the minimum requirements.

8.4 Method of test

8.4.1 Initial conditions

1) Set-up the equipment as shown in annex A.

2) f_offset_CW is the offset between the outer channel edge frequency of the outer channel in the pass band and a CW-signal.

3) The test shall be performed with an f_offset_CW of 1 MHz, 1.8 MHz, 5.8 MHz, 10.8 MHz, 15 MHz and 20 MHz, excluding other pass bands. In addition the test shall also be performed for all harmonic frequencies of the repeaters pass band up to 12,75 GHz.

8.4.2 Procedure

1) Set the Repeater to maximum gain.

2) Set the signal generator to generate a CW-signal, applied to the input port of the Repeater. The power level of the RF input signal shall be at least 5 dB below the power level which, when applied within the pass band, would produce the maximum rated output power, as declared by the manufacturer. This is to ensure that the equipment is operating in the linear output range.

3) The average output power in each case shall be measured using a spectrum analyser connected to the output port of the Repeater and the net gain shall be recorded compared to table 8.3 or table 8.4 whichever is lower.

4) With the same input power as in step 1) set the repeater gain to the minimum specified by the manufacturer.

5) The average output power in each case shall be measured using a spectrum analyser connected to the output port of the Repeater and the net gain shall be recorded and compared to table 8.3 or table 8.4 whichever is lower.

8.5 Test requirements

Table 8.3: Out of band gain limits

Frequency offset from the carrier frequency, f_offset	Maximum gain
1,0  f_offset < 1,8 MHz	60,5 dB
1,8  f_offset < 5,8 MHz	45,5 dB
5,8  f_offset < 10,8 MHz	45,5 dB
10,8 MHz  f_offset	35,5 dB

Table 8.4: Out of band gain limits 2

Repeater maximum output power as in 9.1.1.1	Maximum gain
P < 31 dBm	Out of band gain  minimum donor coupling loss + 0,5 dB
31 dBm  P < 43 dBm	Out of band gain  minimum donor coupling loss + 0,5 dB
P  43 dBm	Out of band gain  minimum donor coupling loss – (P-43dBm) + 0,5 dB
NOTE: The donor coupling loss is considered with 10,8 MHz  f_offset