SimCom SIM808, Проектирование аппаратного обеспечения

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SIM808_Hardware Design_V1.00 2014.03.27 12
Firmware upgrade Firmware upgrading by USB interface.
Table 2: GPS engine Performance
Performance
Parameter Description
Min Type Max Unit
Horizontal Position
Accuracy(1) Autonomous <2.5 m
Without Aid 0.1 m/s Velocity
Accuracy(2)
DGPS 0.05 m/s
Without Aid 0.1 m/s
2
Acceleration
Accuracy
DGPS 0.05 m/s
2
Timing Accuracy 10 nS
Maximum Altitude 18000 m
Maximum Velocity 515 m/s
Dynamic
Performance
Maximum Acceleration 4 G
Hot start 1 s
Warm start 28 s
Time To First Fix
(3)
Cold start 30 s
Autonomous
acquisition(cold start) -147 dBm
Re-acquisition -159 dBm
Sensitivity
Tracking -165 dBm
Channels 22/66
Update rate 5 Hz
Tracking L1, CA Code
Receiver
Protocol support NMEA
Acquisition 42 mA Power
consumption
(4)
Continuous tracking 24 mA
(1) 50% 24hr static, -130dBm
(2) 50% at 30m/s
(3) GPS signal level: -130dBm
(4) Single Power supply 3.8V@-130dBm,GSM IDLE
Table 3: Coding schemes and maximum net data rates over air interface
Coding scheme 1 timeslot 2 timeslot 4 timeslot
CS-1 9.05kbps 18.1kbps 36.2kbps
CS-2 13.4kbps 26.8kbps 53.6kbps
CS-3 15.6kbps 31.2kbps 62.4kbps
CS-4 21.4kbps 42.8kbps 85.6kbps