05.053GPPRadio transmission and receptionTS
The following requirements apply at all frequencies from 9 kHz to 12.75 GHz excluding the relevant transmit bands.
The net out of band gain in both directions through the repeater shall be less than +50 dB at 400 kHz. +40 dB at 600 kHz, +35 dB at 1 MHz and +25 dB at 5 MHz offset and greater from the edges of the BTS and MS transmit bands.
In special circumstances additional filtering may be required out of band and reference should be made to 3GPP TS 03.30.