gps-microphone gps-microphone gps processing standard nmea 2.0 gga and rmc sentences standard nmea...
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GPS-MicrophoneGPS-MicrophoneGPS ProcessingGPS Processing Standard NMEA 2.0 Standard NMEA 2.0
GGA and RMC GGA and RMC sentencessentences
Utilizes SIRF3 based Utilizes SIRF3 based receiverreceiver
Typical accuracy Typical accuracy within 5 meterswithin 5 meters
Data Modem Interface Data Modem Interface FFSK/MSK data FFSK/MSK data
communication over communication over existing voice channel existing voice channel
2400 bits-per-second 2400 bits-per-second data ratedata rate
FEC, CRC, Interleaving FEC, CRC, Interleaving and data scrambling and data scrambling usedused
Messages include 8 Messages include 8 character unit ID character unit ID
GPS-MicrophoneGPS-Microphone
Poll-Based Position Poll-Based Position Reporting Reporting
GPS-Mic always GPS-Mic always responds to responds to location query location query requests from the requests from the BasestationBasestation
GPS-MicrophoneGPS-Microphone
Automatic Position Automatic Position Reporting ModesReporting Modes
1.1. Push-To-Talk (PTT) Push-To-Talk (PTT) switch activatedswitch activated Position report Position report
sent either on sent either on every PTT or a every PTT or a time-throttled time-throttled basisbasis
GPS-MicrophoneGPS-MicrophoneAutomatic Position Automatic Position
Reporting ModesReporting Modes
2.2. Fixed-Time BasedFixed-Time Based Periodic reporting Periodic reporting
of positionof position Time interval Time interval
value : 1 – 255value : 1 – 255 Time interval Time interval
units: seconds, units: seconds, minutes, hours, minutes, hours, or daysor days
GPS-MicrophoneGPS-MicrophoneAutomatic Position Reporting Automatic Position Reporting
ModesModes
3.3. Fixed-Distance Based Fixed-Distance Based Position reported if Position reported if
location change exceeds location change exceeds set distance thresholdset distance threshold
Distance Threshold : 100 Distance Threshold : 100 meters – 64 Kmmeters – 64 Km
Operational modes: Operational modes: absolute (e.g. geo-fence) absolute (e.g. geo-fence) or relative (between or relative (between successive location reads)successive location reads)
Uses separate periodic Uses separate periodic time check which may be time check which may be set by user set by user
GPS-MicrophoneGPS-MicrophonePanic Position Reporting ModePanic Position Reporting Mode
Special “man down” button on Special “man down” button on unit initiates periodic panic unit initiates periodic panic message with position reportmessage with position report
Manual activation/deactivation Manual activation/deactivation button press period is button press period is programmableprogrammable
Rate of reporting to Rate of reporting to Basestation is programmableBasestation is programmable
Basestation can acknowledge Basestation can acknowledge and deactivate through over-and deactivate through over-the-air commandthe-air command
GPS-MicrophoneGPS-MicrophoneOn-Board Memory FeaturesOn-Board Memory Features
Unit can store up to 1500 position reports in non-volatile Unit can store up to 1500 position reports in non-volatile memorymemory
Programmable location storage modes:Programmable location storage modes: Conditional and Temporary Conditional and Temporary
Only used to prevent data loss if currently unable Only used to prevent data loss if currently unable to reportto report
Copy or AuditCopy or AuditLocations are both stored on-board and reported Locations are both stored on-board and reported
over the airover the air Deferred Over-The-AirDeferred Over-The-Air
Locations are stored on-board but not reported Locations are stored on-board but not reported over the air, unless directed to through Base over the air, unless directed to through Base station command.station command.
GPS-MicrophoneGPS-MicrophoneUnit and Basestation Messaging FeaturesUnit and Basestation Messaging Features
High-reliability communication protocol using High-reliability communication protocol using handshakes and retrieshandshakes and retries
Supports Base station broadcast messages to all unitsSupports Base station broadcast messages to all units Efficient time-slot management scheme for unit Efficient time-slot management scheme for unit
responses to reduce probability of collisions and responses to reduce probability of collisions and need for extraneous data messagingneed for extraneous data messaging
Supports Base station multi-cast messages to up to 15 Supports Base station multi-cast messages to up to 15 separate GPS-Mic groups separate GPS-Mic groups Units may be assigned to groups at time of Unit ID Units may be assigned to groups at time of Unit ID
designation and provisioningdesignation and provisioning Can reduce data messaging and simplify equipment Can reduce data messaging and simplify equipment
managementmanagement