User Manual

Page

Next Generation

Signal Enhancement

b. Duplexer

The main function of duplexer is to isolate the uplink frequency from the

downlink frequency, i.e. isolate transmit path from receive path. Two

duplexer units are provided in the repeater, one in the Donor antenna

side and other in the server antenna side. Each duplexer

transfers/receives signals from respective antenna for further

connectivity to low noise amplifier. The bandwidth of the duplex filter

depends on the operator’s frequency band (25MHz, 15MHz, 10MHz,

9MHz, or full Band etc.).

c. Low Noise Amplifier (LNA)

This module is provided after duplexer before the converter. The LNA

provides compensation for the losses suffered by the stream of weak

signals as it passes through splitter/combiner & duplexer (passive

devices). Two LNAs are provided, one each in the UL & DL directions.

d. Converter Module

The basic block of converter module comprises of L.O. frequency

mixer, filter and intermediate amplifier. The low noise amplified signals

are converted to IF in frequency mixer with frequency fed from LO. The

signals are passed through sharply tuned filters. Two numbers of

converters are equipped, one in the DL & one in the UL.

e. Power Amplifier

It is the core module of repeater. It includes driver stage and final stage.

It is installed directly on the heat sink of the repeater. Driver stage and

final stage of power amplifier are in the same unit. Two power amplifiers

with specific frequency bandwidths & gain are provided, one each in the

UL & DL directions.

f. Controller Module (Supervisory)

The man-machine communication between the cellular operator and the

repeater is established through this module. One of the two options as

given below can be used for achieving this objective:

• USB interface

• Wireless modem (Optional)

Remote controlling function of repeater can be achieved by inserting

Wireless modem.

This arrangement also enables status of repeaters at

different locations to be monitored.

g. SERVER Antenna

Server antenna transmits signals from the repeater station to mobile

users and transport received uplink signals from the mobile users to the

base station. Based on the coverage area, a set of select panel

antenna having 60°, 65°, 90° or 120° vertical polarizations with N type