Tyco Electronics M/A-COM MM23016 - Manual (Page 64)

MM23016, Rev. C
64
accomplished by enabling each radio to analyze the signal quality of its current control channel and
compare it with the signal quality of the control channel for each site in its adjacency scan list. (The signal
quality metric used for the ProScan algorithm is based on a combination of both Received Signal Strength
Indicator [RSSI] and Control Channel Verification [CCV] measurements.) When the selected system’s
signal quality level degrades below a pre-programmed level, the radio will begin to look for a better
control channel. Once a control channel that exceeds the pre-programmed parameters is found, the radio
will change to the new system and emit a tone. If the control channel is completely lost the radio, will
enter Wide Area System Scanning and search the programmed adjacent systems until a suitable control
channel is found.
9.9.3 Priority System Scan
The radio can also be programmed for Priority System Scan. (To ensure that this feature operates
correctly, the control channel of the priority system must be located on channel one unless you are using
the ProScan algorithm.) The priority system is the desired or preferred system. While receiving the
control channel of the selected system, the radio will periodically leave the selected system and search for
the control channel of the priority system at a programmable rate. The programmable rate is defined by
the value in the Priority Scan Time control, (unless the ProSound/ProScan algorithm is enabled as
explained below). This priority scan timer is reset each time the PTT button is pressed or when a call is
received. If the priority system control channel is found, or meets the predefined ProScan criteria, the
radio will automatically switch to the priority system.
9.9.4 When Wide Area System Scan Is Enabled
If the radio cannot find the control channel of the selected system and begins Wide Area System Scan
(WA Scan), the radio will only scan for the priority system control channel if the priority system is in the
WA Scan list.
9.9.5 When ProScan Is Enabled
The radio monitors the priority system and will switch to the priority system if the priority system meets
the criteria defined in the “ProSound/ProScan Options” dialog box. If ProScan is enabled, the rate at
which the radio will scan for the priority system is defined by the System Sample Time control.
9.9.6 Menu Selection
Press MENU and then use the ramp control to scroll through the selections until SYS SCAN is
displayed. Then press MENU to toggle the System Scan state. The SYSC ON or SYSC OFF display
message is displayed for two seconds to show the new state.
9.9.7 Pre-Programmed Keypad Key
Press the pre-programmed key and the SYSC ON or SYSC OFF display message is displayed for two
seconds to show the new state.
9.10 GROUP SCAN OPERATION
Only Groups that are part of the radio's scan list will be scanned. Groups are added to the scan list on a
per system basis through programming, the radio keypad, or both, dependent upon programming. This
scan list can be changed by the user from the keypad unless programmed otherwise. Each system's group
scan list is retained in memory when the radio is turned off. The M7200 Series mobile radio can also be