User's Manual

A
PPLICATIONS OVERVIEW
30
SpotCell 100, Release 1.0
SpotCell 100 operates with the following circuit-switched air interface
protocols that are used in the North American (800 MHz) cellular band:

AMPS and NAMPS (analog)

IS-136 NA TDMA

IS-95 CDMA
SpotCell 100 uses two units (DDU and SCU), each supporting full
duplex communications. The DDU is typically located outdoors, at an
elevation higher than the SCU to help reduce the path loss to the base
station. The SCU is located indoors in an area requiring improved
coverage.
The SpotCell 100 system provides a net increase in system gain between
the mobile subscriber and the base station. This gain is distributed
between the active antennas located in the Donor Unit and Indoor Unit
to maximize overall system performance and stability.
The gain is adjusted by the signal processing stages located in the Indoor
Unit to account for the local RF environment changes.
SpotCell 100 uses three main adaptive algorithms to control the system
operation. The first algorithm is used during the system installation, and
determines the position of the optimum base station that the unit
should be aligned toward. This position is presented to the installer as a
green light when the unit is being installed.
The second algorithm performs “intelligent” gain control. This
determines the minimum reliable wireless link to the base station and
the maximum coverage area that can be realized using the available
uplink and down-link gains, so that the system gain is balanced in either
direction.
The third algorithm works to maintain adequate isolation to
unconditionally ensure system stability at all times and therefore
preserve the integrity of the cellular network.