Filter
Top Products
1: Introduction
GP4020 GPS Baseband Processor Design Manual 9
Figure 1.2 above shows a typical GPS receiver employing a GP2015 RF front–end, and a GP4020 correlator. The
RF section, GP2015, performs down conversion of the L1 (1575.42MHz) signal for digital baseband processing.
The resultant signal is then correlated in the GPS correlator within the GP4020 with an internally generated replica
of the satellite PRN code to be received. Individual codes for each channel may be selected independently to
enable acquisition and tracking of up to 12 different satellites simultaneously.
The results of the correlations form the accumulated data, which is transferred to the microprocessor to give the
broadcast satellite data (the ’Navigation Message’) and to control the software signal tracking loops.
Note that the GP4020 is designed to operate from an independent PSU supply, so that it can remain active while all
the peripheral components are powered off. This is signified by the use of the PSU names "Main +3.3V", and
"GP4020 +3.3V". Essentially, the GP4020 can be used with a battery supply while the Main +3.3V supply is
disabled.