Product Description

General function, construction and units
DN991444 © Nokia Corporation Draft 59 (98)
Issue 3-0 en Draft Nokia Proprietary and Confidential
In addition to the DDS and power control functions, the ETXA provides the
controls for all TRX synthesisers. TRX and antenna loop controls are also
provided by the ETXA and from the BB via the I
2
C bus. Time or state dependent
alarms are collected and fed on to the ERXA.
The digital interface includes a PLL part to generate clocks needed for ASICs and
FHSs.
Duplex filter part
The passive duplex filter is connected to the RF module and has a single antenna
connector. There are also customer specific filter modules available for the 900
MHz frequency band.
Mechanics
The mechanics provide an electrical and environmental shield for the unit. In
addition, at higher ambient temperatures it acts as a heat sink, conducting the
dissipated heat out of the units, and at lower ambient temperatures it acts as a
heater.
6.3.3 External interfaces
The front panel interface connectors are described in Table 2.
6.4 Interface unit (VIFA)
The external interfaces of the Nokia MetroSite EDGE Base Station are located on
the interface unit. The Local Management Port (LMP) provides the connection to
the MetroSite BTS Manager PC. The Nokia Q1 interface is a connection for
supervising the Nokia Q1-bus compatible external equipment, such as DMR
radios. The extension interface is used as a databus for BTS chaining.
Furthermore, the interface unit provides connections for ten customer-definable
external alarms and four controls.
The interface unit contains the reference clock source of the BTS that is tuned by
the master TRX, based on transmission or external synchronisation interfaces.
Table 2. TRX interface connectors
Connector Type
Antenna N (female)
2 x RX diversity (In/Out) SMA (female)