User's Manual

Navini Networks, Inc. Ripwave Base Station I&C Guide
55
Install Chassis
There are three types of BTS chassis: Combo, Split and TTA (Figure 23). Prior to Ripwave
Release 1.19 (2.4 GHz systems), only the Combo Chassis was used, but with the licensed bands
(2.3, 2.5, and 2.6 GHz systems) it is allowed to transmit at higher levels of power, which
required better air circulation. This resulted in the introduction of the Split Chassis.
The recently introduced Tower Top Antenna (TTA) chassis, consists only of a digital shelf
because the PAs are incorporated into the base of the RFS. Notice that the TTA digital shelf
includes 8 new additional cards called RF Converters or RFC.
CAUTION! - Please contact Navini Technical support before attempting to
exchange cards between chassis of different type and frequency to verify
compatibility.
CAUTION! – In the TTA configurations, the RFCs output a +24 VDC current,
which is carried to the RFS through the RF Cables. This DC current may damage
test equipment connected directly to the RFC cards or to the end of the RF cables at
the RFS. When connecting test equipment to the output of the RFC card, an
external DC block may be required. Most signal generators and spectrum analyzers
cannot handle DC voltage on the I/O ports. Please, read the caution stickers on the
equipment and provide a DC block if the equipment cannot handle over "0"V DC.
Figure 23: BTS Chassis
TTA ChassisTTA ChassisTTA ChassisTTA Chassis