8 Out of band gain
25.1433GPPRelease 17TSUTRA repeater conformance testing
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 Requirements
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.
In normal conditions as specified in section 5.4.1 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 5 MHz channel within the pass band.
Table 8.1: Out of band gain limits 1
Frequency offset from the carrier frequency, f_offset |
Maximum gain |
2,7 f_offset < 3,5 MHz |
60 dB |
3,5 f_offset < 7,5 MHz |
45 dB |
7,5 f_offset < 12,5 MHz |
45 dB |
12,5 MHz f_offset |
35 dB |
For 12,5 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: The out of band gain is considered with 12,5 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 in TS 25.106.
8.4 Method of test
8.4.1 Initial conditions
Set-up the equipment as shown in annex A.
The test shall be performed with an offset between CW-signal and the first or last 5 MHz channel within the pass band of 2,7 MHz, 3 MHz, 3,5 MHz, 5 MHz, 7,5 MHz, 10 MHz, 12,5 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, for operating bands f ≤ 3,0GHz, or up to the 5th harmonic of the upper frequency edge of the DL or UL operating band, for operating bands f > 3,0GHz.
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 |
2,7 f_offset < 3,5 MHz |
60,5 dB |
3,5 f_offset < 7,5 MHz |
45,5 dB |
7,5 f_offset < 12,5 MHz |
45,5 dB |
12,5 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 |
Carrier frequency |
Maximum gain |
P < 31 dBm |
f 3,0 GHz |
Out of band gain minimum donor coupling loss + 0,5 dB |
3,0 GHz < f 4,2 GHz |
Out of band gain minimum donor coupling loss + 0,8 dB |
|
31 dBm P < 43 dBm |
f 3,0 GHz |
Out of band gain minimum donor coupling loss + 0,5 dB |
3,0 GHz < f 4,2 GHz |
Out of band gain minimum donor coupling loss + 0,8 dB |
|
P 43 dBm |
f 3,0 GHz |
Out of band gain minimum donor coupling loss – (P-43dBm) + 0,5 dB |
3,0 GHz < f 4,2 GHz |
Out of band gain minimum donor coupling loss – (P-43dBm) + 0,8 dB |
|
NOTE: The donor coupling loss is considered with 12,5 MHz f_offset |