User Manual

1 Overview

The Base Station supports three separate Transmit (TX) and Receive (RX) RF-paths

for the three sectors. Each RF path includes a transmitter and a receiver. The actual RF

frequencies for one- and two-sectors will be determined by the customer.

The basic components and process of the Base Station include:

 Downstream (transmit) path description: Digital signals arrive at the WMTS from

the customer’s backbone network. The WMTS Quad Downstream card include a

digital modulator, with output TX IF signal at 44 MHz. This signal is up-converted to

the RF signal, amplified by the Power Amplifier unit, and then delivered through the

Diplexer to the antenna port. A 50-300’ cable is typically connected between the

BSR to the antenna. From the antenna the signal is transmitted to the modems.

 Upstream (receive) path description: RF Signals arrive at the antenna from the

remote equipment. The RX RF signal from the antenna is delivered through the

Diplexer to the Low Noise Amplifier (LNA) and Down-converter module, and then

delivered as an IF signal to the WMTS Hex Upstream receiver card. From there it is

transmitted to the customer’s backbone network.

 WMTS: The Wireless Modem Termination System (WMTS) is the system’s heart.

The WMTS is a mediator between the wireless access system and the customer's

backbone. The WMTS exchanges the digital signal to/from the customer's backbone

with the RF signals to/from the CPE modems. Multiple RF paths terminate in a

single WMTS device.

 Monitoring: The Base Station includes several RF test points to enable local RF

signals measurements, and three monitoring modems to enable remote monitoring

of the base station functionality for each sector. The Base Station also includes a

Remote Control Unit (RCU). It is intended to provide extended BTS monitoring in

future versions.

 UPS: The Uninterruptible Power Supply (UPS) serves as a battery backup for the

whole base station in case of a power down event. The battery backup assures

uninterrupted operation until the external AC Generator goes into operation.

; Note: When a one-sector BTS is built, only channel 1 is used. For two-sectors,

channels 1 and 2 are used. For three-sectors, channels 1, 2, and 3 are used.