Motorola MTX1550 Guide De L'utilisateur page 53

20L01-A_PR_UG_MTX4500.book Page 51 Friday, April 13, 2007 2:47 PM
6. Enhanced Automatic Site Switching
SmartZone radios use RSSI (received signal
strength indication) to determine if the radio
should switch to another site. This is transparent
to the user. In addition, the zone controller
continuously transmits adjacent site information to
the radios, so that the radio, at any time, is able to
quickly switch to the next site that has the highest
RSSI rating. This is an enhancement over AMSS
systems.
7. Preferred Site
SmartZone radios can program certain sites to be
always preferred, most preferred, or least
preferred. This gives the user the flexibility to keep
a radio on a particular site, regardless of the
presence of a stronger signal from an adjacent
site. This also forces the radio to always look for
its preferred site and use it whenever possible.
8. Site Trunking
If the zone controller loses communication with
any site, that site reverts to what is known as "site
trunking." While in this condition, radios are still
able to operate in the trunking mode, but trunking
operations are limited to the site only.
9. Enhanced Failsoft Operation
If a site experiences a complete failure, it reverts
to failsoft operation like today's SMARTNET
system. A SmartZone radio, however, can be
programmed to automatically migrate to the
lowest failsoft frequency programmed in its list of
32 control modes. The radio periodically scans the
control mode to check for the presence of a valid
control mode (in case the radio roamed into a site
which is trunking).
Site Switching in SmartZone
Site Switching in SmartZone mainly uses signal
strength to determine whether or not to switch sites.
Other factors used are the radio's preferred site
selection, and whether the radio is site locked or not.
Because the radio knows the site ID, active control
mode, and the signal strengths of its adjacent sites, the
radio is capable of quickly switching sites.
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Englis