User's Manual

2 Introduction
Page 13
2. INTRODUCTION
2.1. PURPOSE
Cellular telephone systems transmit signals in two directions between base
transceiver station (BTS) and mobile stations (MS) within the signal coverage area.
If weak signal transmissions occur within the coverage area because of indoor
applications, topological conditions or distance from the transmitter, extension of the
transmission range can be achieved by means of an optical distribution system.
Such a system contains an optical master unit and several remote units. The number
of the remote units depends on the hardware and software configuration. The remote
units are connected to the master unit with optical links. The optical loss must be less
than 10 dB inclusive optical couplers or splitters.
The master unit is the connection to the base transceiver stations. The configuration
of a master unit depends on the number of the remote units and the frequency range.
The optical transmission uses Wavelength Division Multiplex (WDM) systems with a
wavelength of 1550 nm in the uplink and 1310 nm in the downlink.
2.2. THE ION-M4/8 19" RU - RF COVERAGE FOR 400 / 800 MHZ NETWORKS
Andrew’s ION-M4/8 19" is a robust, intelligent optical RU to meet designer’s
requirements for high reliability with various redundancy and extension options.
The ION-M4/8 19" is a multi-band, multi-carrier optical RU. It is used in conjunction
with a MU in the ION-M optical distribution system.
This system transports a Tetra, Tetrapol, CDMA or any other signal within up to 4
frequency bands in 400 MHz and the entire 800 MHz IDEN band while providing a
cost-effective solution to distribute capacity from a cluster of base stations.
The ION-M optical distribution system is a cost-efficient coverage solution for dense
urban areas, tunnels, subways, railways, roadways, airports, convention centres, and
other locations where physical structures increase path loss.