User's Manual

Overview Wideband Radio Head
1-4 044-05251 Rev A
Chassis Design
The WRH is housed in a cast aluminium waterproof chassis, class NEMA4 / IP65 approved for outdoor
use but is also suited for indoor installations. The chassis consists of a cabinet and a cover attached
with hinges. The cabinet contains the WRH circuitry. The cover comes as either a low or high version.
The high cover can be used as an empty cover or be equipped as a part of the WRH or an independent
WRH unit. A WRH with a high cover that is equipped as two independent units can, for example, be
equipped for channel selective operation in the cabinet and band selective operation in the cover.
Inside the WRH, a number of amplifier PCBAs are individually shielded and located under a metal
cover that can be opened outward. These PCBAs are of different types depending on the supported
system. Functionally, all WRHs are built up with a number of sub units. These are listed and described
in the following sections.
Sub Unit Overview
A number of amplifier PCBAs are individually shielded and located under a metal cover inside the
WRH. This cover can be opened outward for access. These amplifier PCBAs are of different types
depending on the supported system. All of the WRHs are built up with a number of sub units which are
described in the following sections.
Wideband Amplifier PCBA (WBA)
WRHs can handle multiple carriers over a wide band. Each band requires one WBA for the uplink and
downlink, and one associated PA or MCPA for the downlink. The cabinet can be equipped with up to
two WBAs along with two PAs supporting two bands or one MCPA supporting one band. Positions 1
and 3 are assigned for a WBA.
Power Amplifier PCBA (PA)
The PA is used to amplify the output signal from the WBA in the dowlink direction and reside in
positions 2 and 4.
Multi-Carrier Power Amplifier PCBA (MCPA)
Installed in the WRH-V only, the MCPA is used to amplify the output signal from the WBA. Each MCPA
can handle one band in the downlink direction. It requires an extra heat sink element on the outside of
the cabinet or high cover to dissipate the heat generated. The MCPA occupies positions 2 through 4 in
the cabinet and 6 through 8 in a high cover.
Booster Amplifier PCBA (BA)
A WRH can be modified with a BA on the DL path to increase the output power by 6dB (typically)
depending on system configuration. This BA can operate with a maximum of 2 channels and occupies
position 3 in the cabinet and position 7 in a high cover. It also requires an extra heat sink element on
the outside of the cabinet or high cover. Some configurations use the existing PSU while others require
a second PSU.
Control Unit PCBA (CU)
The CU is the core microprocessor controller in the WRH and is connected to P2 on the DIA. It contains
a microprocessor, main memory, flash memory for the CU software, EEPROM memory for parameters,
memory for the event log and statistics, a REFO reference oscillator, ports for local and remote
communication, battery powered real-time clock, and MAC identity circuit. The CU supervises and
controls operational parameters such as gain control and channel handling, alarms, event log,
password and logon. The CU is also a control interface for OM-Online and OMS. Software for the CU
can be downloaded from OM-Online, either locally or remotely, or from OMS. It is located in the lower
right part of the shielded DIA frame.