MATLAB Code - A Software-Defined GPS and Galileo Receiver: A Single-Frequency Approach - page 138

postprocessing.m

check
parameters, plot
raw data, and
define processing
to be done

signal acquisition

(obtain satellites,
code phase, and
carrier frequency)

signal tracking

(code/carrier
tracking allocated
channels)

position solution

data
remaining to
process?

yes

no

end

FIGURE A.1. GNSS software receiver flow diagram.

mission time, and estimates all pseudoranges. Then the M -file computes ECEF
coordinates of the software antenna and the ECEF coordinates are converted to a
specified coordinate system, say UTM or WGS84.
Finally, the results of acquisition, tracking, and positioning are plotted.

A.2 The settings Structure

All variables common to all receiver blocks, and block-specific variables are
stored in one structure named settings . This approach enables a centralized and
flexible management of the software. For instance, sampling frequency-based pa-