Motorola III - Manual (Page 110)

SmartZone TM Operation
Radios that operate in a SmartZone system will enjoy the benefits that
SmartZone brings over AMSS operation. Like AMSS, SmartZone is a wide-area
coverage system that will allow up to 50 sites to be operational in the system.
SmartZone brings several enhancements over AMSS operation such as:
• Dynamic Site Assignment - Allows the zone controller to dynamically assign
channels at sites where required, as opposed to bringing up channels at all
of the sites as AMSS systems do.
• Variable Density Sites - SmartZone allows sites to have varying numbers of
channel resources to accommodate low-density areas as well as high-density
areas.
• Automatic Site Registration/De-registration - SmartZone radios automatically
send in their unit IDs and current mode selections upon power up, power
down, site switches, mode changes, and when they exit emergency
operation. This allows the zone controller to know where the radio is at all
times, and also what mode the radio has selected.
• Critical Site Assignment - One or more sites can be designated as critical
sites. This will instruct the zone controller to ensure that, before a channel
grant is given to a radio that has been identified as a critical site user, every
site that is designated as a critical site must have available channel
resources, otherwise a busy will be sent to the unit.
• Busy Override - This feature allows a SmartZone radio to send a busy
override request if a busy is issued. The zone controller will send a grant
even though not all of the sites may have available channel resources.
• Enhanced Automatic Site Switching - Smar tZone radios will use RSSI
(received signal strength indication) to determine if the radio should switch to
another site; this will be transparent to the user. In addition, the zone
controller continuously transmits up to seen adjacent site IDs (along with
their active control modes) to the radios, so that the radio, at any time, will
be able to quickly switch to the next site that has the highest RSSI rating,
since the control mode and site ID is known in advance. This is an
enhancement over AMSS systems.
• 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.
• Site Trunking - If the zone controller loses communication with any site, that
site will revert to what is known as “site trunking.” While in this condition,
radios will still be able to operate in the trunking mode, but trunking
operations will be limited to the site only.
• Enhanced Failsoft Operation - If a site experiences a complete failure, it will
revert 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 will
periodically scan the control mode to check for the presence of a valid
control mode (in case the radio roamed into a site which is trunking).
109
109 Trunked Radio Features Operation
(cont.)