Manual Part 6

HCU Hybrid Combiner Unit
1 Product Overview
The HCU contains three hybrid combiners. Each hybrid combines two RF
signals, delivered from the dTRU, into one. This signal is then passed to the
Combining and Distribution Unit (CDU), and provides an expanded capacity
using a minimum number of TX/RX antennas. (It is unnecessary to increase
the number of TX antennas or to build a new site.) The HCU covers both the
GSM 800 and GSM 900 standards. The insertion loss is up to 3.3 dB.
1.1 Variants
The HCU is available for GSM 800 and GSM 900.
2 Dimensions
The physical characteristics of the HCU are shown in the table below.
Table 1 HCU Size and Weight
Height Width Depth Weight
22 mm 482.6 mm (19in.
standard)
236.6 mm
(1)
2.6 kg
(1) The HCU protrudes 42 mm from the rack (excluding connector).
3 Function Description
This section describes the function of the HCU.
P011003A
SUBUNIT 1
TX1 TX2
LOAD
TX1+TX2
SUBUNIT 3
TX1 TX2
LOAD
TX1+TX2
SUBUNIT 2
TX1 TX2
LOAD
TX1+TX2
Figure 1 Block Diagram for the HCU
A dTRU has an internal hybrid combiner, which can combine the two
transmitters into a common output. A CDU-G has no further combining function
3 (6)
EN/LZT 720 0449 Uen R2A