Huawei BTS3900 V100R003, Описание аппаратуры

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l Receives UL RF signals from the antenna system and then down-converts the received
signals to IF signals. After amplification, analog-to-digital conversion, digital down-
conversion, matched filtering, automatic gain control (AGC), the IF signals are sent to the
BBU for further processing.
l Implements power control and Voltage Standing Wave Ratio (VSWR) detection
l Provides reverse power detection
l Provides frequency synthesis and loopback test
l Generates the CPRI clock, recovers the CPRI clock from loss of synchronization, and
detects alarms
l Supports 40 W (2 carriers) and 80 W (4 carriers) power outputs
Principle
The WRFU consists of the high-speed interface unit, signal processing unit, power amplifier,
and duplex unit.
Figure 4-37 shows the principle of the WRFU.
Figure 4-37 Principle of the WRFU
The high-speed interface unit has the following functions:
l Transmits the signals received from the BBU to the signal processing unit
l Transmits the signals received from the signal processing unit to the BBU
The signal processing unit consists of two UL RX channels and one DL TX channel.
l The UL RX channel has the following functions:
– Performs down-conversion of the RF signals to IF signals
–
Amplifies the IF signals and performs IQ demodulation
– Converts analog signals to digital signals
–
Samples digital signals
– Performs matched filtering
–
Performs AGC
– Encapsulates data
l The DL TX channel has the following functions:
– Decapsulates the clock signals, control signals, and data signals from the BBU and sends
them to associated units
–
Shapes and filters DL signals
4 BTS3900 Components
BTS3900
Hardware Description
4-50 Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
Issue 04 (2011-02-15)