7 Out of band gain

3GPP51.026Base Station System (BSS) equipment specificationPart 4: RepeatersRelease 17TS

7.1 Test purpose

To test the net gain of the repeater outside the relevant MS or BTS transmit band. This test shall also check the net gain at harmonic frequencies.

7.2 Test case

The repeater shall be set to maximum gain. In case of a channel selective repeater, two of the channel selective modules shall be set to the lowermost and the uppermost ARFCN within the repeater’s pass band.

A continuous sinusoidal RF signal shall be fed successively at frequency offsets Y from the edges of the relevant MS or BTS transmit frequency band into the relevant input port of the repeater. The frequency offsets Y shall have the following values:

400 kHz, 600 kHz, 800 kHz, 1 MHz, 5 MHz, 10 MHz, 15 MHz, 20 MHz.

This shall be repeated with an RF input signal successively set to all harmonic frequencies of the repeaters pass band up to 12.75 GHz (i.e. multiples of the centre frequency of the repeaters pass band up to 12,75 GHz).

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

The average output power in each case shall be measured and the net gain shall be recorded.

The measurements shall apply to all antenna ports of the repeater.

Test environment: Normal

Extreme temperature

7.3 Conformance requirement

The net gain in both directions through the repeater shall be less than:

– 50 dB at 400 kHz offset and greater;

– 40 dB at 600 kHz offset and greater;

– 35 dB at 1 MHz offset and greater;

– 25 dB at 5 MHz offset and greater;

from the edges of the relevant MS or BTS transmit bands.

7.4 Reference requirement

3GPP TS 45.005 [13], annex E.