User's Manual

Table Of Contents
Unit Descriptions - RF Path CMA-331-AEN Page 44
Draft
2.1.3 IHU (Integrated Headend Unit)
The IHU combines both HEU and OIU functionality in a single compact chassis. The IHU interfaces to the RF sources (via RIM
modules), conditions the signals, performs the RF to optic conversion of the received signal and distributes the wireless RF
services to the RAU units over the fiber optic infrastructure to the remote site.
Figure 2-14. IHU Front Panel with Installed Modules
Note: The IHU also includes a pre-assembled Cable management Tray with routed ERFC cable (not shown in Figure 2-14)
used for connecting the RIX and OIX modules.
IHU hosts the following modules:
1. HCM- Headend Control Module; overall system management module (see section 2.1.1.1)
2. ACM Auxiliary Control Module; provides interfaces for management of domestic modules via HCM (see section 2.1.1.2);
installed in IHUs in configurations with more than one IHU
3. RIM - Radio Interface Module; RF source conditioner (see section 2.1.1.3); Up to four RIMs in Slots 2-5 (marked in RED); Up
to four additional RIMs in ‘Combo’ Slots 6 9 (marked in WHITE)
4. RIX - Radio Interface Expander; RF to optic interface module (see section 2.1.1.4); One RIX is installed in the IHU - Slot 1
RIX installed in IHU supports expansion connections to one additional IHU or HEU.
5. OIM Optical Interface Modules; converts the RF to three Optical links (see section 2.1.2.2); Up to four OIMs in Slots 10 13
(marked in BLUE); Up to four additional OIMs in ‘DUALSlots 6 9 (marked in WHITE)
Note: Each IHU supports up to 8 SM optic fibers (one fiber per OIM), which are routed to up to 24 RAU (three Remote
Access Units per OIM).
6. OIX - Optical Interface Expander; RF to optic interface Module (see section 2.1.2.3); One OIX is installed in the IHU - Slot 14;
OIX installed in IHU supports expansion connections to one additional IHU or OIUU.
7. PSM- Power Supply Module; AC or DC power supply (see section 2.1.1.6).