2.1 RRU Functions
This section describes the main functions of the RRU.
The Remote Radio Unit (RRU) performs the following functions:
l
Receives downlink baseband data from the BBU and sends uplink baseband data to the
BBU.
l
Receives RF signals from the antenna system, down-converts the signals to intermediate
frequency (IF) signals, amplifies the IF signals, and performs analog-to-digital conversion.
The transmit (TX) channel filters downlink signals, performs digital-to-analog conversion,
and up-converts RF signals to the TX band.
l
Multiplexes receive (RX) and TX signals on the RF channel, which enables these signals
to share the same antenna path. It also filters the RX and TX signals.
l
Provides a built-in Bias Tee (BT). The built-in BT couples RF signals and OOK signals
and transmits them through the TX/RX port A. The built-in BT also supplies power to the
tower mounted amplifier (TMA).
l
The RRU can be powered by the AC/DC power module. In this case, this RRU is called
AC RRU. For details about the AC/DC power module, see the
AC/DC Power Module User
Guide
.
2.2 RRU Exterior
This section describes the exterior and dimensions of an RRU.
shows an RRU.
Figure 2-1
RRU exterior
shows RRU dimensions.
RRU3942
Hardware Description
2 RRU Introduction
Issue 02 (2012-06-29)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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