Service Manual

GSM-205-323
SURF module
31st Oct 01
Tech. 5–24
Technical Description: Horizon macro indoor
CONTROLLED INTRODUCTION
68P02902W07-B
SURF module
SURF module
overview
The sectorized universal receiver front end (SURF) module is located in a slot at
the rear of the cabinet top panel. Three connectors on the underside of the
module connect to the SURF harness which provides connectivity to up to six
compact transceiver units (CTUs). Antenna connections are located on the top
of the unit.
There are six types of SURF module available for the Horizon
macro indoor BTS,
depending on the frequency variant:
 850 (MHz) single band SURF.
 900 (MHz) single band SURF.
 900 (MHz) dual band SURF.
 1800 (MHz) single band SURF.
 1800 (MHz) dual band SURF.
 1900 (MHz) single band SURF.
The single band SURFs contains three amplifier sections for connection to three
pairs of receive antenna inputs providing reception at the appropriate frequency.
The 900 dual band SURF contains three amplifier sections for connection to
three pairs of antennas providing 900 MHz reception and, being dual band, a
further amplifier section for connection to a pair of 1800 MHz receive antennas.
The 1800 dual band SURF similarly contains three amplifier sections for
connection to three pairs of antennas providing 1800 MHz reception and a
further amplifier section for connection to a pair of 900 MHz receive antennas.
Each amplifier section provides two receive outputs which may be directed to
any of the six CTUs, by the switch section. There are three connections to each
CTU; RxA, RxB and loopback test (L).
The two receive outputs from amplifier 0 are split and may be used as
extensions to other cabinets if required. These act as extended antenna
connections from antenna 0. The extension cables are connected to the
receive antenna connection ports on the SURF of the extension cabinet (which
is able to respond to each amplified signal as if it were a normal antenna input).