1. Trunk amplifier, also maned cable amplifier, is mainly used to compensate for power loss caused by signal transmission and distribution in the passive indoor distribution system.
2. The trunk amplifier is an active device. In the indoor distribution system using a trunk amplifier, it is necessary to consider the influence of the noise figure of the trunk amplifier on the downlink sensitivity of the distribution system and noise elevation on upstream of the whole distribution system.
3. The upstream and downstream gain regulation of dry amplifier can not only ensure that the upstream gain won't cause the system pressure is too high, and can also guarantee the effective transmit power of the antenna port of the amplifier branch. It should be noted that the appropriate upstream and downstream gain regulation can ensure the balance between upstream and downstream.