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DAN189
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EXAR UARTS IN GPS APPLICATIONS
April 2008
EXAR UARTS IN GPS APPLICATIONS
1.0 INTRODUCTION
This application note describes where an Exar UART can be used in a Global Positioning System (GPS)
application. GPS has traditionally been used in military applications such as marine navigation, aircraft
navigation, and weapon’s guidance. However, GPS applications have recently expanded to industrial and
consumer applications such as vehicle navigation systems, fleet management, and personal navigation. In
these applications, the Exar UART can be used in the GPS receiver and in the GPS application.
1.1 GPS Receiver
A GPS receiver typically includes the following:
• RF block for receiving the GPS data and converting it to digital data
• Microprocessor for processing the data
• ROM to store the firmware for processing the data
• RAM used by the microprocessor for data processing
• UART to send data to the GPS application
The figure below shows a block diagram of a GPS receiver.
F
IGURE 1. GPS APPLICATION EXAMPLES
FIGURE 2. GPS RECEIVER BLOCK DIAGRAM
GPS Receiver
UART
UART
TX
RX
RX
TX
GPS Applications
Marine Navigation System
Aircraft Navigation System
Vehicle Navigation System
Fleet Management System
Personal Navigation System
RF Block
Microprocessor
ROM RAM
UART
TX
RX
