Falcom GmbH 051-1-1 ユーザーズマニュアル

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Description
GPS receiver
A2D–JP
Version 1.03
Side 23
6.2
Product overview
The GPS receiver requires conditioned 3,3 V DC power and a GPS 
signal from a passive or active antenna.
The 12 channel architecture provides rapid Time-To-First-Fix 
(TTFF) under all start-up conditions. As long as visible satellites are 
not obscured, acquisition is guaranteed  under all  initialisation con-
ditions. 
To minimise TTFF when main power is removed from the GPS re-
ceiver SRAM with external DC supply voltage and EEPROM are 
used to archive RTC time and prior position data.
Communication with the GPS receiver is established through two 
asynchronous serial I/O ports. The GPS receiver's primary serial 
port outputs navigation data and accepts commands from OEM ap-
plication in NMEA-0183 format or CONEXANT binary format.
The secondary port is configured to accept differential GPS (DGPS) 
corrections in the RTCM SC-104 format.
6.2.1 GPS receiver architecture
Figure 7: GPS receiver architecture
The functional architecture of the GPS receiver is shown in Figure 7. 
The GPS receiver design is based on the Conexant Zodiac chip set,  
the RF-Monopac and the Scorpio DSP, which contain the required 
GPS functionality. The RF-Monopac contains all the RF down-con-
version and amplification circuitry, and presents the In-Phase (I) and 
Quadrature-Phase (Q) Intermediate.