Four ways to improve capacity and coverage are:

1. Micro-zone cell concept

2. Cell sectoring

3. Cell spltting

4. Repeaters

Use of Repeater for range extension.

• It is often necessary to provide the dedicated coverage of the cellular mobile radio system for hard-to=reach areas such as within building or in valleys or in tunnels.

• The radio transmitter known as repeaters are often used to provide such range extension capabilities. The repeaters are bidirectional in nature.

• They simultaneously send signals to and receive signals from a base station.

• The repeaters work using over the air signals so that they may be installed anywhere and are capable of repeating an entire cellular or personal communication (Pcs) BAND.

• The repeater amplifier's and re radiates the base signal, signals to the specific coverage region after receiving signals from a base station forward link.

• At the same time, the received nose and interference are also re radiated by the repeater on both the forward and reverse links.

• Therefore we must takes proper care to p;ace the repeaters properly and to adjust the various forward and reverse link amplifier levels and antenna patterns properly.

• In practice, the directional antennas or distributed antenna systems (DAS) are connected to the inputs or outputs or repeaters for localized spot coverage., particularly in tunnels or buildings.

• The repeater does not add capacity to the cellular system, nut it simply serves to re-radiate the base station signal into specifications.

• The repeaters are increasingly used to provide coverage into and around buildings, where coverage has been traditionally weak.