User's Manual

Chapter 1 - System Description The Base Transceiver Station
4Motion 20 System Manual
1.3.1.6 AVU
The 2U-high AVU includes a 1U-high integral chamber for inlet airflow and a
1U-high fan tray with an internal alarm module. To support high availability, the
fan tray includes 10 brushless fans (9 fans are sufficient for cooling a fully-loaded
shelf). Fan failure is indicated by both the front panel LEDs and a trap sent to the
management system. To further support high availability, the chassis may
operate without the hot-swappable fan tray for up to 10 minutes until the AVU is
replaced.
1.3.2 The Macro Outdoor BTS
The Macro Outdoor BTS is a modular scalable and reliable all-outdoor platform
enabling extended and flexible installation capabilities while sustaining all the
features and capabilities of the 4Motion solution.
The All-Outdoor Macro BTS portfolio includes the following system elements:
 NAU (Network Access Unit): A full-size enclosure containing NPU and AU
cards.
 DAU (Dual Access Unit): A full-size enclosure containing two AU cards.
 SAU (Single Access Unit): A half-size enclosure containing one AU card.
The full-size enclosure is similar to the enclosure of the 4x2 ODUs (see
Section 1.3.3), supporting flexible mounting options for system components,
including back-to-back and side-by-side mounting. The units are available with
either full (4-channels) AUs or with 2-channels AUs.
The modular architecture and different unit types enable building a variety of
configurations using up to six AUs with either 2 or 4 channels, addressing a
pay-as-you-grow deployment. The functionality is the same as described for the
NPU (see Section 1.3.1.2) and AU (see Section 1.3.1.3) cards of the Indoor Macro
BTS, with a few minor exceptions.
Table 1-2: PSU Requirements, Configurations with one NPU (excluding PSU
redundancy)
Number of AUs Minimum Required Number of PSUs
1 - 4 2
5 - 6 3