User Manual

MBF, Multi Band Repeater

PRODUCT DESCRIPTION AND USER'S MANUAL

1 Repeater Technology

1.1 Basic Repeater Features

A basic feature of a mobile communication system is to transmit RF signals between base stations and mobile

radio equipment.

When there is a blocking object, such as a mountain or a building, preventing the base station signal to reach

the mobile equipment, a repeater can be used to extend the base station’s coverage area.

Repeater

BTS BTS

Donor antenna

Server antenna

Undisturbed transmission Obstacle creating a coverage hole

MS MS

In the downlink path (from the base station to the mobile phone) the repeater picks up the signal in the air via

a donor antenna, amplifies it and re-transmits it into the desired coverage area via a server antenna. In the

uplink path (from the mobile phone to the base station) the repeater receives the signals from mobile

transmitters in the covered area and re-transmits them back to the base station.

A repeater can work off-air, as the repeater in the example above, or be fed over fibre from an optical master

unit, OMU. The OMU taps the signal directly off a base station via a coupler, converts it to light and

transmits it to a number of repeaters via fibre.

1.2 Repeater Types

1.2.1 Channel Selective Repeaters

Channel selective repeaters are mainly used for coverage of dead zones, shadows, in-building coverage or

other areas with inadequate signal strength. The output power of a channel selective repeater is sufficient to

cover an area shadowed by a building or other obstacle.

In a channel selective repeater each carrier is separately filtered, amplified and retransmitted.

BTS

Donor antenna

Server antenna

Repeater

A channel selective repeater system consists of one repeater unit complemented with one antenna facing the

donor BTS and another antenna directed towards the coverage area. The repeater site needs to be located