5 BTS3012AE RF Front-End Subsystem

About This Chapter

The BTS3012AE uses the DAFU subrack to perform the functions of the RF front-endsubsystem. These functions include transmit/receive duplexing, transmit signal combining,receive signal diversity, low noise amplification of receive signals, and related control functions.

5.1 Components of the BTS3012/BTS3012AE RF Front-End SubsystemThe functions of the BTS3012/BTS3012AE RF front-end subsystem are performed through theboards in the DAFU subrack. The DAFU subrack can be configured with the DDPU, DCOM,DFCU, DFCB, or the combination of these modules.

5.2 Functions of the BTS3012/BTS3012AE RF Front-End SubsystemThe BTS3012/BTS3012AE RF front-end subsystem duplexes the received and transmittedsignals, combines the signals for transmission, divides received signals, and amplifies the lownoise of the received signals.

BTS3012AEProduct Description(for DCU) 5 BTS3012AE RF Front-End Subsystem

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5.1 Components of the BTS3012/BTS3012AE RF Front-EndSubsystem

The functions of the BTS3012/BTS3012AE RF front-end subsystem are performed through theboards in the DAFU subrack. The DAFU subrack can be configured with the DDPU, DCOM,DFCU, DFCB, or the combination of these modules.

Internal Composition

Part A in Figure 5-1 shows the DAFU subrack configured with the DDPU and part B in Figure5-1 shows the DAFU subrack configured with the DFCU.

Figure 5-1 Fully configured DAFU subrack

DDPU

0 1 2 3 4 5

DDPU

DDPU

A

DFCU

DFCU

DFCU

0 2 4

B

NOTE

l A maximum of six DDPUs can be configured in the DAFU subrack. The DCOM is used with the DDPUonly when a cell is configured with more than four TRXs.

l At present, the DFCU is applied only over EGSM 900 M frequency band. It is used only in S4/4/4 orhigher cell configuration.

l If the DAFU subrack is only configured with the DFCU, up to three DFCUs can be configured. TheDFCB is cascaded only with the DFCU during the expansion of the DFCU, enabling the six-in-onefunction.

l The DDPU and the DFCU can be configured in the same subrack.

5 BTS3012AE RF Front-End SubsystemBTS3012AE

Product Description(for DCU)

5-2 Huawei Technologies Proprietary Issue 01 (2007-09-10)

External CablingFigure 5-2 shows the external cabling of the BTS3012/BTS3012AE DAFU subrack.

Figure 5-2 External cabling of the BTS3012/BTS3012AE DAFU subrack

Signal cables betweenthe DCTB and the DAFU subrack

DDPU/DFCU/DFCB

RF RX signal cableDAFU subrack

RF TX signal cable

RF jumper

5.2 Functions of the BTS3012/BTS3012AE RF Front-EndSubsystem

The BTS3012/BTS3012AE RF front-end subsystem duplexes the received and transmittedsignals, combines the signals for transmission, divides received signals, and amplifies the lownoise of the received signals.

The RF front-end subsystem performs the following functions:l Combining multiple routes of RF TX signals for transmission

l Transmitting and receiving signals through a duplexer

l Detecting and reporting antenna Voltage Standing Wave Ratio (VSWR) alarms and lownoise amplification alarms

l Controlling the low noise amplification gain

l Detecting and reporting the transmit power on the antenna ports

l Detecting and reporting the temperature of the boards

l Detecting whether a board is in position

l Supporting online software upgrade

BTS3012AEProduct Description(for DCU) 5 BTS3012AE RF Front-End Subsystem

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