| Dynamic
Control Channel |
In
the event that exclusive channels are unavailable, the
system may operate on shared channels, if a number are
available, by moving the control channel among them,
not leaving it active on any one for a long period of
time, thus allowing co-channel users to share the channel.
The length of time the control channel stays on any
one channel depends upon the number of shared channels
available and their activity level. Seamless handoff
is accomplished with overlap to collect marginal units.
|
| Dynamic
Transmit Power Control |
The
RSSI of field units, and frame error rates, is monitored
and strong signals cause a reduction in transmitter power
which increases battery life and decrease spectrum pollution
and blocking of nearby units. |
| Echo |
A
diagnostic mode which allows a mobile or portable unit
to test coverage by transmitting a voice message to a
repeater, and hearing it play back from the site. The
frame errors on both uplink and downlink are numerically
displayed, along with signal strength, in the mobile radio,
and quality of service is aurally determined. |
| Embedded
GPS |
Each
transmission from DWC Base/Repeater, Mobile or Portable
contains available GPS information obtained from the GPS
receiver present in every mobile and portable model. DB-1000
repeaters also have embedded GPS receivers, in order to
transmit GPS ephemeris data to mobiles, generally in specialized
systems that require very fast cold-boot GPS fixes. |
| Emergency
Alert Button |
The
Emergency Alert Button present on every mobile and portable
allows an alarm to be sent to the control station or console
which results in a distinctive audible warning signal.
The initiating unit can send this silently, with no external
indication of this happening, or can send an audible alarm
from the local speaker. |
