Reference Manual

3(10)
EN/LZT 720 0244 R1A
1 Product Overview
The DXU-21 is a CPU, which acts as an interface between the transmission
network and the transceivers. It also extracts timing information from the PCM
link and generates a timing reference for the RBS. The DXU also performs
supervisory tasks.
The DXU-21 transmission interface has long-haul capability and can be run on
both 1.544 Mbit/s (T1) and 2.048 Mbit/s (E1) PCM links.
1.1 Main Functions
The DXU serves as the Central Main CPU node and its main functions are:
• Provides the RBS with an interface to the transport network through four
fixed E1/T1 transmission ports
• Handles incoming traffic, controls and supervises information and sends it
to its destination within the RBS
• Provides frequency reference signals and timing signals for circuits within
the RBS
• Stores and executes RBS SW stored on a removable flash card
• Controls the climate and power system
2 Dimensions
The DXU-21 has the following dimensions:
Table 1 Size and weight
Height
Width
Depth Weight
227 mm
(6 HE x 44.45 mm)
71 mm
(14 TE x 5.08 mm)
240 mm 2.4 kg
3 Power Consumption and Heat Generation
Table 2 Power consumption and heat generation
Max. Power Consumption Max. Heat Generation
40 W (typical 30 W) 40 W