User's Manual

3 Detailed Description
16 APCD-LM043-4.0
The CCU routes IP packets received from the CCU radio port
• to internal CCU processes,
• through the CCU Ethernet port to any router on the Ethernet network, such as the
Network Access Point, or
• back out the radio port to other EUMs (EUM-to-EUM packets).
The CCU routes IP packets that are received from the Network Access Point through the
Ethernet port
• to internal CCU processes, or
• through the radio port to the destination EUM.
The CCU can be installed in a standalone configuration, or in a CCU shelf, as shown in Figure
9, with other operating and backup CCUs. The CCU is powered by an AC/DC power supply,
which can also stand alone or be installed in the CCU shelf. The CCU operates independently
of other CCUs and can be swapped out without interrupting the operation of other CCUs.
Figure 9 CCU Shelf
Up to four CCUs can be installed at the same CAP, as follows:
• Up to three operating CCUs, each with its own cavity filter, lightning protector,
transmission line, and antenna.
• One backup CCU, if CCU redundancy is provisioned. Since the backup CCU is
“switched” into the RF circuit of the failed CCU, by the RFSM, it does not require its
own cavity filter, lightning protector, transmission line or antenna.
The CCU comes with a setup antenna, which can be used during CCU configuration and test,
prior to deployment.